Windows-designed and/or tzdb-compliant software can and does handle these changes regularly, so unless the implementation is bonkers (which means it is hardcode

Windows-designed and/or tzdb-compliant software can and does handle these changes regularly, so unless the implementation is bonkers (which means it is hardcoded and someone should be fired like this alarm clock designer: https://news.ycombinator.com/item?id=25647903 https://news.ycombinator.com/item?id=25647903), it is an embedded software, or it was literally hours before the transition, it should just work with a simple change in registry (Windows, usually handled by updates) or text files (tzdb).