In the same file at line 590 the OldLog is set to "$LOGS/p4verify.${OldLogTimestamp}.log" but prior to this change the old log file was "${LogToRotate}.${Datestamp}". As an example (after locally addressing the issue above), the new format naming results in p4verify.2023-05-09_09-40-05.log whereas the old name was p4verify.log.2023-05-09_09-28-17 so the files no longer sort the same. I *think* it was an intentional change to retain the .log extension on files but don't see it called out on https://swarm.workshop.perforce.com/projects/perforce-software-sdp/jobs/SDP-829 unless it fell under "general log file handling"?
Additionally, the previous time format was '%Y-%m-%d_%H-%M-%S' but is now '%Y%m%d-%H%M%S' so there aren't as many spacers for readability.