sorry lads,should have explained it in more detail,firstly the pics are after laying on,not after 4 hrs,the best way i can describe this plaster is it's like a bucket of self leveller but worse,there are different manufacturers of this plaster,i've used two types but characteristic's are much the same,i've been plastering for 40 years(yes i know it's sad,another dinosaur)used loads of different plasters,in my opinon this is one of the harder one's to use.At the source of heat 600mm above and 300mm side and bottom of fire to be plastered,but the client wanted all the breasting plastered with it,there is a base screed as well.After approx 4 hrs some patches were still wet and most of the area was ok,anyway gave up on the patches at 5pm went back next day and managed to trowel up,
(sorry should have posted final pics).