It's currently 110ppl (95 RON) and 117ppl (diesel) in Liverpool. I've not been to Costco yet this week but going by past experience they're usually 3ppl cheaper for unleaded (making 107ppl for 95RON and 109ppl for 97RON super).
BP on the A45 into Birmingham was 106.9 on Saturday... starting to wonder if that was a pricing error as I've not seen it that cheap anywhere else since.