Hi I’ve plastered a friends bedroom a couple of weeks ago, all the plaster is now dry apart from some patches which is still dark and not dry he’s had the heating on and also the window open for ventilation I’m beginning to panic as he’s wanting it painting is there anything I can do he’d had some issues with water damage originally from a leaky roof which he’s had resolved. I had to hack some plaster off where there had been water damage and waited 2 weeks before bonding and then a week later I skimmed 2 coats one of the damp patches is not where the plaster was previously damaged so my question is, is there anything I can do any advise is appreciated as I’ve just qualified I’ve attached a photo the three dark patches at the top is where the damage was originally and I bonded and the bit on the right hand side of the cupboard was not where the damage was.