Looks like they stepped in right on the 50 day sma & previous resistance around 375 ish. Do you get any perks if you hold Tesco shares like you do with other companies? Like double Club Card points or something like that?
........... that is compounding the problem here. They were around before the update/results and are still present. You've only got to look at the number of automatic trades going through on Level 2 to see that.