Your bookable hours are the hours your price list prices. To change your regular hours, edit the opening days and times of your price variants. To close for a day or a few hours, block the courts in the schedule instead.
Change your regular hours
Go to Settings → Price Lists → Standard Price Lists and open your list.
Click ⋮ on a price variant, then Edit.
Change Opening days and times.
Click Save.
Repeat for every variant in the list.
A time stays bookable if any variant still prices it, so check them all.
Close for a day or a few hours
Don't change your price list. Block the courts instead:
Go to Calendar → Schedule and go to the date.
Click or drag over the times and courts.
Under Booking type, choose Unavailable.
Choose a Reason.
Click Create.
Different hours for a season or holiday
Create a special period price list with those dates and the hours you want open. See "What's the difference between standard and special period price lists?"
Good to know
The Club opening hours on Settings → The Club are shown to players for information only. They don't change which times can be booked.
How far ahead players can book is set separately, under Settings → Rules & Limits → Booking Rules.
If a special period price list is active on a court, change the hours on that list, because it replaces the standard list.