Have ephemeral JIT runners started enforcing an idle minutes limit?

Recently, we've been observing an increased number of ephemeral JIT runners being removed from the server after listening for jobs for 2 to 6 minutes, mostly close to 6 minutes.

Has GitHub started enforcing an idle minutes limit for ephemeral JIT runners? If so, what is the limit, and is there any documentation about it?

Example 1

Sep 16 15:14:45: √ Connected to GitHub
Sep 16 15:14:46: Current runner version: '2.337.0'
Sep 16 15:14:46: 2026-09-16 15:14:46Z: Listening for Jobs
Sep 16 15:16:47: The runner no longer exists on the server. Cleaning up local configuration.
Sep 16 15:16:47: √ Removed .credentials
Sep 16 15:16:47: √ Removed .runner
Sep 16 15:16:47: Runner listener exit with 0 return code, stop the service, no retry needed.
Sep 16 15:16:47: Exiting runner...

Example 2

Sep 16 17:26:15: √ Connected to GitHub
Sep 16 17:26:16: Current runner version: '2.337.0'
Sep 16 17:26:16: 2026-09-16 17:26:16Z: Listening for Jobs
Sep 16 17:32:17: The runner no longer exists on the server. Cleaning up local configuration.
Sep 16 17:32:17: √ Removed .credentials
Sep 16 17:32:17: √ Removed .runner
Sep 16 17:32:17: Runner listener exit with 0 return code, stop the service, no retry needed.
Sep 16 17:32:17: Exiting runner...

Start with the ephemeral JIT runner lifecycle described in the issue, especially the “Listening for Jobs” and “The runner no longer exists on the server” log entries. Determine whether the observed 2-to-6-minute removal reflects an enforced idle limit, and identify the applicable limit or documentation; the issue names no repository file or test to run.