shared albums no longer working on phones despite working on macbooks (after Dec 15...)

I am trying to shared a photo album from my macbook pro with family (& myself) on their iphones. This was working just fine December 15th and before, but since then no updates appear on any phones in our family, nor will newly created shared albums show up on phones, despite that face that they show up on macbooks in the family. Seems like Apple blocked sharing from macbooks to phones after Dec 15? Already tried restarting phone, tried turning off shared albums on phone and turning back on after 10 min. This is a problem on at least 3 phones, so doubt it is a problem with all 3 phones, which makes me think Apple is somehow blocking the xfer? The source of the photos is a MacBook Pro (14-inch, 2021) running 12.7.1. My own phone with same appleid is also failing to receive any updates or new shared albums, despite running iOS 26.2. The only solution I have not tried is signing out of icloud on my phone. I could try that, but that will remove 12 payment sources on my phone, and it is time consuming to add them all back, so want to avoid that unless there is some reason to believe that might be the problem.