time.mktime read ps's local lstart, which is ambiguous in the hour a DST change repeats: the start could come out an hour off and a live holder be taken for a reused pid (or the reverse). ps now runs with TZ=UTC0, which BSD ps and procps both honour, and calendar.timegm reads it. No /proc. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>