As stated in title, would be great if we could know how many hours and minutes left before the next exchange can be done, just like the Pumpkin box exchange. It would make it much more convenient if we were to coordinate several characters. I roughly know the next timing (every 4 hours) and I may arrive earlier by 10 minutes or by 1 minute but I have no way of finding out. That said, if it's a lot of work for this 1 week event then I guess it can't be helped.
Well the previous event didn't have something like that either so I assume it's either really hard to implement or they just haven't thought of it. A +1 here because that would be really nice. Also would be nice to add an option to check how many times you've turned in items except when you're already turning in(I've had alot of people whisper to ask how to check amounts and there wasn't really a way except for turning in one more item/set.)
I'm not sure if the developers have the time to make this minor QoL changes as they are quite busy preparing for Christmas.