You can do a 1 day block. It starts at checkin and ends at checkout, so it goes over a night, so it looks like 2 days but that’s how reservation systems work. Guests don’t book days, they book nights. So in effect, a 1-day block is really a 1-night block.
It would not make sense to block 1 day, really. I guess you’d be saying a guest staying the previous day would have to check out at midnight and someone coming the following day would be able to only check in midnight or later on that same day. Does that make sense?
