It's the old points on the lighter choices beans (PP don't have half points). The PP for them are 4 per half tin. It's 8 points for a whole big tin. Don't know about the Sainsburys beans sorry.
I'd be more concerned about the date on that tin of beans, they started using Propoints in what, Nov 2010? Packaging in Tescos would have been updated within 6 months, I know tins keep a while, but I'd check the date lol