Glossary A–ZLetter C
Clock change (summer time)
The clock change is the switch between standard time and summer time, in Germany between Central European Time (CET) and Central European Summer Time (CEST).
In the EU, summer time begins on the last Sunday in March and ends on the last Sunday in October.
In Germany the clocks go forward from 2 am to 3 am in March and back from 3 am to 2 am in October. On the changeover day in March, the hour between 2 and 3 am is therefore missing, while in October it occurs twice. A player with a correctly configured time zone adjusts itself, and schedules based on local time carry on as usual. Content scheduled for 2.30 am, however, may be skipped in March and play twice in October.
If only a fixed offset from UTC is configured instead of a time zone, such as UTC+1, the device does not adjust and is an hour out in summer. A look at a few devices after each changeover is worthwhile. Playback reports and logs should be stored with the time zone, so that the repeated hour in October remains unambiguous. Time zone rules arrive with operating system updates; very old devices may have outdated rules.