How many time in advance can a student sign up for a one to one conversation?

I’ve noticed that some hours before the available 1 on 1 conversations, it appears the “No more times available…” message.
For example, I had from 22:00 to 00:00 available yesterday, but a student tried to sign up at 18:00 (4 hours in advance) and he got this message.
So, do you know which is the deadline time to sign up for a 1 on 1 conversation?

I suppose you can sign up for 1-on-1 only 12 hours ahead. At least this Tuesday I tried to enlarge my Japanese class, but can’t as it was less than 12 hours ahead. So I booked the nearest available 1-on-1 slot and it was exactly in 12 hours. (Later we arranged with my tutor and moved this 1-on-1 earlier)

That’s right. It is 12 hours ahead so that tutors can have some idea of when they have upcoming conversations.

Thank you for your quick answer Cakypa and Mark. 12 hours ahead, got it!

cool this is a good idea