https://ibb.co/F6KB5nS
https://ibb.co/98SLbxr
https://ibb.co/8dQNWt8
three pictures for you.
basically, its a tiny section 8cm high 12cm wide. very small. no peeling paint, no peeling lining paper etc.. 'powder' can be removed with just my finger no need for a wet cloth. if removed with finger returns 1-2 days later..if removed with bleach and water, returns 5 days later. damp coursing is three bricks high as photographed.. this is clearer futher along as you can see the 'skin'.
any advice or input would be great :)