On my booking page I have the ability to book up to 24 spots. There is a drop down. It allows the customer to click on the time and shows there are multiple spots available. But when you go to select 1 spot, 2, 3, etc. They are all greyed out and unable to book.
@danmath we are aware of an issue with fixed start/end dates and group bookings. This should be fixed tomorrow. In the meantime you can remove the fixed dates (under where you set availability). If needed you can use Calendar Managed Availability to mark specific spots on your calendar.