Hi slider, at the moment I've got no dates for anything and I'm not sure if they will give access to the network API which some games have on the Playdate Catalog. If there's demand and I can do it for both the Catalog and the itch version I would probably add a leaderboard just for fastest level completion times which makes the most sense.
So the main choice is simply, if you buy on the Catalog it's part of your Playdate account and will update automatically. If you buy here you just have to sideload and update yourself when there's a new version.