Some towns have more than one big Tesco. I wonder if they have considered staggering the Sunday opening hours so that one of them opens, say 0800 to 1400 and the other opens, say 1200 to 1800?
In Stevenage there are two large Tesco stores, on Sundays one opens 10am-4pm, the other opens 12noon-6pm.
The Sunday Trading Act in England and Wales came in during 1994. Basically stores with less than 280 square metres of selling space can open any hours they like.
Stores with a selling area greater than 280 square metres may only open for six hours between 10am and 6pm (half an hour 'shopping up' time is allowed and customers can select goods before the store opens as long as they don't pay for them until the store opens).
Large stores must close on Easter Sunday and Christmas Day. All other bank holidays are unregulated and stores may open any hours they choose.
The previous Sunday Trading laws had become a farce as they prescribed what types of goods could be sold (there was a farcical situation where you could buy a magazine but not a bible!) The 1994 Act was a compromise between what the retailers and Government of the day wanted and the opposition of religious groups and the Keep Sunday Special Campaign.
Every few years it there is speculation that the six hours rule for large shops will go, although (suprisingly) many of the large retailers have little appetite for extended Sunday trading (possibly because the big retailers now have large numbers of small stores which would be affected if large shops could open all hours on a Sunday. Note that between 4pm and 8pm on a Sunday is often the busiest time of the week for a small store)
During the Olympics in 2012 the six hours rule of large stores on Sundays was suspended and I expected this to become permanent, however this proved not to be the case as many large stores did not even open for any additional hours.
I can't see the six hour rule for large stores on Sundays changing any time soon.