Good luck with all this, SRS. We only had one small ceiling go here (my fault, slipped with a spanner doing some plumbing and foot went through kitchen ceiling) and that was messy enough, although there was a bit of water involved too.

The new ceiling was an improvement though. The old one had some marks presumably caused by past problems. And we no longer felt constrained by the holes for downlighters (I think fitted for mum when she first moved in but never a good solution). We changed to one central fitting with 6 (LED for a few years) spots which provide a much better spread of lighting where you want it in that particular work area.