I think you added the links in an edit?

The Science cite shows something that's very different than what people might take from your comment. Briefly, prior infection plus one mRNA dose induces a very good immune response, much better than a single dose without prior infection. It does not compare two mRNA doses against prior infection.

I believe the cite I provided does support the idea that coronaviruses vary, in particular that HCoV-229E exhibits continuous genetic drift. But here's an excellent paper that goes into a lot more detail on that: https://journals.plos.org/plospathogens/article?id=10.1371/j...