I’m still having problems with sync. Upon opening Drafts for Mac, I could tell that it didn’t reflect changes in a note (“Nobody Notes”) that had been changed on my iPhone. I kept waiting and waiting (over 15 minutes). All my machines are on the same network. Finally, it was only after I actually clicked on the note in Drafts for Mac that it updated.
I had the same problem recently. I was editing a Draft on iPad and those changes just disappeared. In the versions I couldn’t find the newer Versions of that Draft. I do have some problems with my wifi though. Still I would hope that changes would be saved locally and synced later, if there was actually no internet connection temporarily.