Covid isn't just going to go away sadly. I think 2021 is going to be fairly similar to 2020. The only thing that can stop that is that if the roll out of the vaccine is efficient and they hit the targets they have set.
Scientists are saying that maybe by August we could have hit the 70 to 80% mark of total number of people vaccinated. However there are people who think this is overly ambitious and it could even be 2022 before the final less at risks groups get theirs.
Lets hope it's the former and we get this under control soon. However I don't think this coming year will be a good one for theme parks yet again. Social distancing almost certainly isn't going away for a good chunk of the year.
I think there’s one key thing that will shape the vaccine rollout and speed at which restrictions are removed in Britain, and that is the approval of the Oxford vaccine. I know that the Pfizer vaccine we’re currently deploying is more effective, but Britain has far more doses of Oxford’s vaccine, and it is also easier to deploy in a wider range of situations. As such, speedy vaccination will be far, far easier once Oxford’s vaccine is approved.
The government is saying that Oxford’s vaccine should be approved by the end of 2020. As such, I personally think that things will look significantly better as we move towards spring/summer 2021. I think the first quarter of 2021 (January, February, March) could possibly be quite difficult, but as we move into the second quarter (April, May, June), I think things will significantly improve.
Even excluding the impact that mass vaccination will have, COVID cases will naturally decrease as we move towards the spring and summer, anyway, as from what we’ve seen, its transmission seems to be seasonal (higher in winter, lower in summer).
EDIT: On that note, approval of the AstraZeneca vaccine is now anticipated to be coming “within days”:
https://apple.news/AN3-7X9tpTGm_zpBQcV6Nxg