Hello all. I have been plastering for 30 years & I would consider myself very experienced. I have always used pva on over skims, I have tried blue grit on the last few re skims due to there being vinyl silk paint on walls & ceilings as I have found that pva is not ideal on this type of background unless a shovel full of sharp sand is added. I skimmed a kitchen & dining room about 3 weeks ago & used blue grit on everything except plasterboard. I got a call today from the customer telling me that the kitchen ceiling skim is coming off in large areas after the painter attempted to paint it. The other walls that I had skimmed that had blue grit on apparently seem 100% but the ceiling has failed to adhere properly. The finish that I used was carlite finish which is the most common finish in Northern Ireland. Any ideas as to what caused this? I left the blue grit overnight to dry. Cheers