We're currently in a position where infections are rising quickly but hospitalisations and deaths remain low. Going 'back to normal' as in no distancing restrictions or requirements for masks in shops, offices, medical settings, cinemas, gyms, nightclubs, restaurants, bars or at home etc means that infections at least are likely to accelerate further. Hopefully serious illness and hospitalisation will remain very low, due to where we are with vaccinations.
However, it should be recognised that it's not going to be long before the first people to be vaccinated will need boosters, so that's now going to be an ongoing thing, albeit on a smaller scale as not everyone will feel the need to continue to be vaccinated. Will it just be a GP led service, or will some of the mass vaccination centres remain in place?
But the two great flies in the ointments are the requirements to isolate when testing positive and the restrictions that are almost certainly going to be on foreign travel.
Isolation is hugely disruptive to education, employment etc so that can't continue indefinitely, but I don't know what the plan is in this respect.
Then, if we do have a massive case load, we're probably going to be effectively banned from travelling abroad or having visitors from abroad, because from the point of view of other countries, we will be high risk travellers who will require us to quarantine. After all, by our own criteria, we're a red list country.