Well, I'm no expert, but I have made two successful mirrors (6" & 8") with full thickness blanks and moderate f/ratio (8 & 6.5). For mirrors like these, I'm not aware of any advantage to letting them cold press for days. In fact, Texereau warns against leaving the tool and blank together for too long <i>after<i> polishing, because he claims it could lead to microripple. What might happen at the micro-level <i>before<i> the figuring spell, I don't know. But if you use rouge (as I do) for figuring, you could end up with two very stuck- together disks, if they dry out. I've come close to this after an hour's cold pressing in a warm room.
Unless, you have a very short f/ratio, or want 1/50 wave optics, I couldn't see doing anything different from following Texereau's advice. But others in this group have a lot more experience than I do.
Roger Honpi@uh.edu