Just been to asda @ telford town centre and picked up a 4pint semi-skimmed milk. Shelf said £1.19 (I think) and is on offer @ 2 for £2, but I went to self service and it scanned as 50p.
Definitely not reduced for date reasons, it's got display until 30th Apr, use by 7th May.
I do have receipt, and barcode is 20337087.
No idea if it's nationwide or a local bargain, check your receipts!!