Ok, thanks.
I'd purchased two tins of Weathershield just over a year ago but as last Summer was so bad, I never used it. So I thought I would phone Dulux and see if those tins would be affected. They say outside paint is not affected (I guess in the same way anyhow). However, they have also repeated what has been said on here, that Water based White Gloss is the only gloss which does not yellow. But.......
I have already coated some skirting and a door in Solvent based primer and undercoat and Dulux say that for Water based gloss, it has to be water based primer and undercoat.
Any ideas what I could do to recover from what I have already painted?
Sand and try with water based undercoat? The Primer will be difficult to remove now under I hard sand but the doors were stripped by a heat gun and took ages.
Thanks