For the "Edit scheduling links" feature, we should have the ability to edit the options available for the "Advance Notice" dropdown/picklist. For example, I think that "18 hours" or "20 hours" is a big omission.
Let's say I work 9AM-5PM and a client goes to my link at 5PM to book time, I'd be OK with them booking me tomorrow at 11AM or later.
But I'm not OK with them booking time with me at 9AM because I may not see that until I start working at 9AM the next day. 12 hours is too short and 1 day is too long.