The system is handling dates and timestamps based on the time zone of Brussels (Central European Time). Note that,
If a given date is a start date, then the related decision will take effect at the beginning of the day, i.e., at 00:01;
If a given date is an end date, then the related decision will take effect at the end of the day, i.e., at 23:59.
Dates, that are shown to the user, also correspond to the time zone of Brussels and are displayed following the format DD/MM/YYYY.