Also, for those weary about mixing vaccines, here is an article that discusses this. It looks promising.
https://www.bloombergquint.com/coronavirus-outbreak/pharma-executives-seeking-higher-immunity-mix-own-covid-shots
“If you can mix and match, it’s going to look better, something that immunologists have known for decades,” said Danny Altmann, professor of immunology at Imperial College London. “I’d bet my house on the working hypothesis that it’s doable and would produce immunity that’s at least as good if not better.” Early research appears to back the approach. A study of almost 700 people in Spain showed that those who received a second dose of Pfizer’s vaccine after a first Astra shot saw their neutralizing antibodies climb sevenfold, significantly higher than those who had two Astra doses. A small trial in Germany suggested that mixing Astra and Pfizer shots could trigger antibody responses almost four times higher than a two-dose course of the Pfizer vaccine."