It sounds like I did miss quite a lot of change, as of 2016 or 2017 I could still walk around pretty much anywhere on both levels and all of the main frescoes were still exposed (although a lot of material was still covered under plaster ... ostensibly for preservation). there was an minbar bar in the apse but it was skewed at an odd angle in a way that looked like it hadnt been used in quite a long time.

Did they cover up the frescoes in the pendentives of the main dome that depict the (very much non-human looking) seraphim?