When I had the mac app running along with the iOS app, I always used the mac app to switch on scheduling for new stacks that I wanted to begin studying. It has just occurred to me that there was a reason for this, and I think it may have been per instructions you wrote on this forum at some point. Because having dispensed with trying to sync the mac app to the iOS, I used the iOS app to turn on a stack's scheduling a couple of months back. Having reloaded the mac app and synced, I happened to notice that while the scheduling and grading data for this stack of notes has synced to the mac app, the actual selection of the long-term scheduling option did not sync, and so the stack was not showing as being scheduled. The cards all show only one instance of having been studied-- that is they have the data from the first time they were studied and graded on Nov 20th, but nothing beyond that was synced. The notes of that stack will all show a recent run of 1 correct or 1 incorrect, and regardless of that all show next scheduled due date as Nov 21st. There are 23 notes in the deck.

Am I now remembering this right that you have to use the mac app to turn on scheduling if you want this to sync correctly between the apps?
(If so, I guess that would mean that anyone that starts of using the iOS app that wants to begin using the mac app will have to contend with the fact that they will lose their study history?)