The Lead time feature prevents those last minute bookings and gives you the time required to prepare for your meetings.
To set the Lead time for a meeting, select the meeting and navigate to the "WHERE" tab, here you'll find the lead time setting. You can see some default lead times and an option to add a custom lead time as well.
Also you can to set your lead time as granular as you needed, it can be set in minutes, hours or even days depending on how much time you need before invitees can book meetings with you.
Let me show you an example, let's say I'm setting my lead time as 2 days, and I'll save it.
If I open up the booking page now, notice that a booking can't be scheduled within the next 2 days.
If I troubleshoot and select the 19th, you can see that the reason for not being able to book a meeting is the lead time of 2 days.
Now the host will have a a minimum gap of 2 days from when the meeting is booked to the actual meeting time.
So make sure to set the lead time based on your needs to avoid those last minute surprises.