if its a reskim mate id knock up again for the topping. dunno the circumstances but if its anything other than fresh board and you want it bang on, for the sake of a decent finish its worth the extra imo...
I'd just look at it as a p'ss easy set, take the paper...
could mean the difference between a recomendation or not..
thing is, dont top it too quick or you might as well just throw one thick coat on..
does depend on the wall though, if its near enough to start youll prolly get away with it but you need to be pretty good to get a decent finish (no orange peel, no tiger stripes) in one coat...(which topping with the same mix is)..
ive just done a fresh board ceiling, 6x3m garage conversion so i could reach it off the floor... 3 hours as opposed to 2..
could have put one coat on but i gave it two, perfect finish, blokes a small builder and there'll be more where that came from..