Don't skip crons when time jumps forward due to DST #541
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We're investigating a production bug at Monzo where a 2:00 AM US/Pacific cron was skipped on 2025-03-09. We discovered the root cause is the https://github.com/robfig/cron library skips jobs that are scheduled during the interval when time jumps forward due to DST changes.
It seems the library's behavior is a bit non-standard in this regard, and differs from ISC cron which is used in most distributions of Linux and BSDs:
This PR aligns the behavior of the library with ISC cron.