diff --git a/generated/cr-buildbucket.cfg b/generated/cr-buildbucket.cfg
index 792d51d..278da36 100644
--- a/generated/cr-buildbucket.cfg
+++ b/generated/cr-buildbucket.cfg
@@ -182,7 +182,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -226,7 +226,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -271,7 +271,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -314,7 +314,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "v8": false'
@@ -359,7 +359,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -404,7 +404,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -450,7 +450,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -496,7 +496,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -541,7 +541,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -584,7 +584,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -629,7 +629,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -674,7 +674,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -720,7 +720,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -765,7 +765,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -810,7 +810,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -856,7 +856,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -902,7 +902,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -949,7 +949,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -996,7 +996,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -1042,7 +1042,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -1085,7 +1085,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -1396,7 +1396,7 @@
         '      "pool": "luci.flex.ci"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-ci-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -2151,7 +2151,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -2195,7 +2195,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -2240,7 +2240,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -2283,7 +2283,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "v8": false'
@@ -2328,7 +2328,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -2373,7 +2373,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -2419,7 +2419,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -2465,7 +2465,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -2510,7 +2510,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -2553,7 +2553,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -2598,7 +2598,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -2643,7 +2643,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -2689,7 +2689,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -2734,7 +2734,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -2779,7 +2779,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -2825,7 +2825,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -2871,7 +2871,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -2918,7 +2918,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -2965,7 +2965,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -3011,7 +3011,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  },'
         '  "xfa": true'
@@ -3054,7 +3054,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
@@ -3535,7 +3535,7 @@
         '      "pool": "luci.flex.try"'
         '    },'
         '    "execution_timeout_secs": 1200,'
-        '    "expiration_secs": 10800,'
+        '    "expiration_secs": 300,'
         '    "service_account": "pdfium-try-builder@chops-service-accounts.iam.gserviceaccount.com"'
         '  }'
         '}'
diff --git a/main.star b/main.star
index cd47c00..1b2a94a 100755
--- a/main.star
+++ b/main.star
@@ -18,7 +18,13 @@
     "tree_status_host": "pdfium-status.appspot.com",
 }
 
-_SWARMING_TEST_TIMEOUT = 20 * time.minute
+# How long to wait for a swarmed test task to start executing. If the task fails
+# to schedule, the swarming pool probably is busy, and the PDFium recipe falls
+# back to executing the test locally.
+_SWARMING_TEST_SCHEDULE_TIMEOUT = 5 * time.minute
+
+# How long to wait for a swarmed test task to finish executing.
+_SWARMING_TEST_EXECUTION_TIMEOUT = 20 * time.minute
 
 # Dicts for OS-specific dimensions.
 _LINUX_FOCAL_DIMENSIONS = {
@@ -187,8 +193,8 @@
         properties.update({
             "swarming": {
                 "dimensions": dimensions,
-                "execution_timeout_secs": _SWARMING_TEST_TIMEOUT / time.second,
-                "expiration_secs": luci.builder.defaults.execution_timeout.get() / time.second,
+                "execution_timeout_secs": _SWARMING_TEST_EXECUTION_TIMEOUT / time.second,
+                "expiration_secs": _SWARMING_TEST_SCHEDULE_TIMEOUT / time.second,
 
                 # TODO(crbug.com/1465963): Ideally would be a test-only account.
                 "service_account": service_account,