I passed it a few months ago and I had no idea what what happening - I saw the scaffolding and just assumed it was a bit of maintenance.
I passed it again this week and saw the new glass so did some research.
A couple of photos from tonight.
and search for
16/01858/FUL
And it looks from the photos that they have cladded the concrete instead of cleaning it. A pity really as it distracts from the main original design feature of the building - brutalism concrete.
It also looks like level 1 has an outside door.