//It is absurd that if I, as an office worker were pinged (if I had the app), I'd have to isolate, but if I worked in Tesco and were pinged, I wouldn't have to isolate.//
What's more absurd, dd, is that nobody has to do anything. You don't have to have the app and you don't have to comply with its advice if you are pinged. That's why I don't understand why the government is setting up a "scheme" to exempt some employees from certain businesses. Exempt them from what?