The vaccines only really need to be for the elderley and highly vulnerable for life to get back to normal . Hoping the roll out for those groups can be pretty quick.
That would be the common sense approach. I expect the opposite will happen.
The elderly and vulnerable stand a much higher chance of having an adverse reaction to a vaccine, particualrly because of the range of drugs they will likely already be taking. If instead you take the approach of vacinating those most likely to pass on the virus, you can rapidly bring down the R rate with fewer complications. We got close in the summer, before everyone scattered to the four corners on their summer holidays and strangely the infection cycle kicked in again.
It is counter intuitive but my theory is that the most effective way to protect the vulnerable will be to ensure they don't come into contact with the virus.