[tass]

I'm going off the assumption that the capacity has been expanding as much as possible, so scrap factories wouldn't be a problem.

The Pfizer vaccine seems to have a shelf life of 6 months, so realistically the earliest they could have begun mass manufacture and have an effect today would have been June. That's right around the time they narrowed down to a single vaccine candidate.

I'm surprised that mass manufacturing didn't begin back then with the only possible candidate, especially since the US government also put their order in around that time. I can't find a whole lot of info on when they did ramp up (something I saw said October), and what reasons they had for not starting earlier.