[xiphias2]

That's totally fine, but they could have finished the Phase-3 testing for old people, or at least offer alternative vaccines if the measured immune reaction is too small.

Right now my parents are opting waiting 1-2 months more for the Pfizer/Moderna vaccines, because after they decide on a vaccine, even if the antigen count in their blood is small, it doesn't give them the right for another vaccine (in UAE the government provides a 3rd dose of Sinopharm for people with small immune response).