As more elderly persons are vaccinated it increases the young as a percentage being seriously ill but they are less likely to proceed to death and so the death rate should be falling - and the evidence points to that. The model needs to find a tolerable level of illness and deaths (no death being 'acceptable') and then Covid19 becomes a flu-like illness which allows the economy to function as 'normal' (or 'new normal'). There are signs in the UK that this is happening but may be derailed by future more aggressive variants (with recombination of two different viruses being the worst-case scenario).