iMessage photos missing after upgrade

Hi all,

I recently upgraded from my iPhone 12 Pro (running iOS 15.6) to the new iPhone 14 Pro (running iOS 16.0.2) and went the route of the direct phone-to-phone restore, however noticed that a number of photos (~58) were missing in the Photos app.

Upon checking for some of the missing photos it seemed to be only photos received through iMessage that had been shared to the Photos app (didn't check all, but the ones I found were received from others. I have "Show in Shared with You" enabled on both devices).

I also noticed that the Messages app did not display any received photos in the info page for the conversation thread (press the recipients name/ photo). The app had several days to finish indexing (and the indexing message disappeared), links and documents were present, but no photos. All photos remained in the message thread, but not on the info page.

I decided to reset my phone and restore over iCloud, but to no avail. Same problem.

I then disabled Messages in iCloud on my old device and performed another reset + restore, and it seemed to have solved my problem. Both devices showed the same number of photos and I could see all received photos under the individual thread's info page.

However a few days later I noticed that most of these photos had again disappeared– for one particular conversation, instead of showing 30+ photos, it only showed 4. Returning to the Photos app I noticed the exact same number of photos, ~58, were missing.

I performed another reset + restore and at first all the data was there, but on the 2nd day (in-between here I changed no settings, didn't even use the new device) I had the same problem with photos missing from the Messages app and Photos.

Has anyone else experienced the same? Could this be a bug in iOS 16 (and thus something that would be fixed)? Are there any other restore tricks I could do to alleviate this issue? I only have a few more days before I need to return my trade-in device and wanted the phone to be all set up by then. Thanks!