Provavelmente, depende da sua implementação do cron, mas o popular Vixie cron afirma no manual:
cron then wakes up every minute, examining all stored crontabs, checking each command to see if it should be run in the current minute.
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Special considerations exist when the clock is changed by less than 3 hours, for example at the beginning and end of daylight savings time. If the time has moved forwards, those jobs which would have run in the time that was skipped will be run soon after the change. Conversely, if the time has moved backwards by less than 3 hours, those jobs that fall into the repeated time will not be re-run.
Only jobs that run at a particular time (not specified as @hourly, nor with '*' in the hour or minute specifier) are affected. Jobs which are specified with wildcards are run based on the new time immediately.
Como a alteração do horário de verão foi menor que 3 horas, seu programa seria executado pouco depois das 3:00
Não tenho certeza se esse é um comportamento específico do Vixie cron, parece que me lembro de como meu PDP-11 funcionou bem nos anos 80, mas não tenho certeza.