Can I restrict access for a specific person or group of persons to certain times?

Yes, you can restrict access to certain times by setting a timetable.
1. Tap on the “Persons” symbol in the menu bar.
2. Tap on the clock symbol at the top right.
3. Tap on “+”.
4. Define the desired time slot, e.g. Monday, Wednesday and Friday from 7:00 to 09:00.
5. Tap on “Save”.
6. Tick the desired person.
7. Tap on “Save”. A clock symbol now appears for the desired person in the person overview.