Add exceptions to the Time Restriction rule for last-min bookings

With the current logic, a message is rescheduled to the nearest 9. However, with last minute bookings, it's possible for a booking to be made after the time has been rearranged to. In an instance with a user, the CO message was missed as it's rescheduled time fell before the booking was actually made. Allow for messages like these to take priority over the rule, or allow them to be rescheduled for the next available time i.e. 9am.