Did /me/drive/special/photos/delta?expand=thumbnails just stop working in Graph?

For 2 years, I have been using the endpoint 

https://graph.microsoft.com/v1.0/me/drive/special/photos/delta?expand=thumbnails to sync the latest photos from special OneDrivephotos folder including thumbnails.  3 days ago, suddenly started getting a 400 error on the URL.  So if I remove the expander, the endpoint works but now location:{} is empty too.

So did I miss a notification that features going away?  Or is Graph seeing some issues right now?  

You can also reproduce in Graph Explorer with personal OneDrive.

Any one else seeing this behavior?