I'm painting the exterior woodwork. 1st top coat on after all the prep and I've realised the colour doesn't work (lighter too orangey brown for the house). Does it matter if I switch brands for the final coat? I'm using sandtex exterior gloss and I'm pretty sure they don't do the brown I want. Will I need to sand down again or can.i just slap on some dulux or whatever brand is the right colour? Thanks