I think what what we are seeing now is probably close to being the new normal of a few years. New strains appear and there is a low level wave of new infections, despite the best efforts of the vaccination programme.
I suspect Boris will delay the 21 Jun reopening, but sooner or later he will have no choice be to accept the new norm and put in place his permanent plan, as global data will basically show that this is something that comes and goes and we will just have to adapt and learn to live it.