Just went to my local Tesco Express and scanned in a box of Birds Eye Chicken Chargrills. Sticky and Sweet bbq flavour.
These were advertised for £1.58. There was no promotion, and this was not a yellow label deal. When I scanned it, it charged me 0.44p.
So I went back and grabbed another 2 boxes and again, they scanned for 0.44p.
Not sure if this was intentional, national, or just a mistake at this store alone. Haggerston London.