hangs head in embarrassment ..the holes in the door seal are drainage holes ...haha, what a blonde! Actually, in my defence, I knew about two drain holes but I'm sure I'd never noticed these extra 2 smaller ones before. I had wondered but they didn't look symmetrical enough to be intentional (apparently due to dried soap powder residue). And I'm not the first to call him about the same thing.
Anyway, as he supplied and fitted it in the first place he was very pleased to see it's doing so well...and it's good news for me, a few bob saved for now. Cherry tree needs pruning though... :(