It looks like it'll stay at 12C + with not a lot of wind, but I want my legs covered. Any way I've done it seems to be just as warm/hot as each other, so I'm just going for the winter bib tights, but with a base layer and normal long sleeve jersey. Probably just use mitts too. I'll have a waterproof and long gloves in the bag just in case.
Might be on the warmer side, but I'd rather that than too cold.
I'll be ready to go at 11pm, but I'll meet you at Tesco. What time are you looking at getting there?