@Daniel1127 I have never heard of the "24 hours from making a reservation rule".
And even if there was such a thing, it would not apply to you.
Unless the "24 hour" rule is a Federal, State, or Local law, the only check-out time rule that applies in your house is "Daniel's Check-Out Time Rule", which is whatever you say it is.
You have 100% authority over check out time.
Let the guests know that.
Guest: So I have 24-hours from when I make a reservation to check out.
Daniel: Nope. Check out time is 11 am.
Guest: But that's not 24 hours from when...
Daniel: Are you arguing with me? Now check out time is 10 am.
Guest: But...
Daniel: Check out time is now 9 am. Want to keep arguing?
Guest: ...
Daniel: See you in the morning.