Again, I'd advise not to book and pay for travel so far out.
In my eyes the Post Covid-19 travel world will be much different that we were getting used in 2019 and earlier on.
In the future governments will quickly shut borders and restrict travel at short notice, once, an infectious disease is spreading. That may include an agreesive flu variant, MERS or a Coronavirus mutation.
So we may have survived Covid-19 by November 2021, all it takes is another virus scare (another Ebola spread in West Africa) and travel is going to be shut down again.

So solution -> book flights/travel only a short notice and if the prices are too high, change the travel destination or abandon the travel plans alltogether. I am pretty sure that the travel market will adjust to this new reality.