A bunch of Googling and StackOverflowing didn’t give any good answers to this, so I wonder if the following fact pattern speaks deeply to any of the sleuths on this blog.

  1. Not all notes on my phone sync to my Mac. The last note that synced is from August 20. I’ve created plenty of notes since then.
  2. Notes are correctly syncing from phone to iCloud. I confirm this through iCloud.com.
  3. If I make a change to a note on iCloud.com, that change is reflected immediately on the phone but is not reflected on the Mac. Likewise if I create an altogether new note through iCloud.com. So both the phone→iCloud and iCloud→phone directions work fine.
  4. If I create a new note on the Mac, it doesn’t show up on iOS.
  5. If I edit the aforementioned August 20 note on the Mac, I would expect the August 20 note to move to the top of the list of notes on iOS and iCloud.com. It does not. In fact it looks like that note is only on the Mac, not on iOS or iCloud.com. If I instead pick a note from August 8 that is on the Mac, on iOS, and on iCloud (this is a note containing thoughts I jotted down as I read the book about Nixon, as it happens), and I edit that note on the Mac, those edits don’t show up on iCloud.com or on iOS.

    What I conclude up to here is that Notes from the Mac is just not talking with the rest of the world at all.

  6. iCloud drive from the Mac works fine: I create a note in TextEdit and save to iCloud Drive, and it appears in the iCloud Drive app on iOS. This would seem to suggest that the Mac is having no problem reaching iCloud.
  7. I use lots of other iCloud services from the Mac, including Messages. iMessages sent from the Mac show up on iOS instantly.
  8. Logging out of iCloud on the Mac, then logging back in, doesn’t change things: the latest note on the Mac is still from August 20.
  9. Both iOS and Mac (and, indeed, iCloud.com) are configured to use the same user ID, so that’s not the problem.
  10. I’m syncing notes with multiple accounts (iCloud, home, work), but the problem isn’t that the missing notes are on another account: even if I display ‘All Notes’ on the Mac, I don’t see the post-August 20 notes.
  11. Phone is running iOS 9.1 beta 1. Mac is running OS X Yosemite 10.10.5.

I wish Mac stuff — particularly the networking layer — were easier to debug. Console.app doesn’t seem to have much to say on the Mac side, and I wouldn’t even know where to begin debugging the iOS side. And for all I know, this problem doesn’t exist on either the Mac or iOS; instead, maybe the problem is somewhere out in the æther in one of Apple’s server farms.

I’m curious if other people know what might be going on here.

Update (2015-09-13): I’m told that the iOS 9 beta asks me, the first time I run Notes there, whether I want to upgrade their format to some new version. I don’t remember this, but it wouldn’t surprise me if I said yes to it without paying much attention. If I did say yes to it, then I’ll need to upgrade to El Capitan through the beta program. I’m in the middle of doing that. We’ll see if that fixes this problem.

Update 2 (2015-09-13): Yep; updating to El Cap solved it. So it was just a beta-software incompatibility … though would I have suffered the same problem had I waited until iOS 9 was no longer in beta, and updated then without updating my Mac to El Cap?