SLUDGE WHERE ARE YOU?

I'm painting a room in my house Dulux Matt Almond White. It's on to fresh plaster so I gave it a mist coat on Sunday (plasterer finished on the 24th so it was definitely dry) and the first coat on Wednesday. When I went back last night to give it a second coat, areas were darker and patchy, especially where I'd used a brush to cut in. I gave it a second coat, this time using a mini roller to get as close as possible to the corners but some bits are still darker, the worst being the corner in the photo.

That photo was taken this morning, 13 hrs after the 2nd coat. Should I expect it to even out with more drying time or do I need to do something different?

The room is pretty cold at the moment because the radiator's off, if that has any bearing on drying times or anything

image0.jpg