Just noticed this, I had a bunch of albums in folders, and they got kicked out of the folders into the root of the hierarchy, all out of order. Took me some time to fix it all. Strangely this happened after I updated my Apple TV, *NOT* the phone or iPad. I disabled iCloud Photo Library on the ATV since I never use it there anyway, in case it was at fault. Anyone else ever seen this? It's pretty concerning.