Hi everyone,
Hope you are all keeping safe.
Just after some advice on this wall in one of the rooms in our house, we have just purchased and this area has had some water damage in the past however the source has been resolved.
The plasterboard isn't similar to what I have seen before and wondering if anyone can recognise what type it is from the attached pictures?
The darker ones are where water damage has happened.



Cheers,
Reg