I have more than 3 decades experience doing mass distributions of relief materials overseas. The key to making it orderly and user friendly is distribution design.
My initial design suggestions include:
Conduct a highly promoted mass registration based on census, voter and tax rolls.
Allow people to identify their vaccination cohort such as by age or conditions.
Let people know their confirmed cohort, vaccination location and estimated month of vaccination as early as possible.
As time gets closer, update via TV, IMs, etc., until you can provide a day and 2 hour time window for the actual vaccination.
Conduct the vaccinations at flow through locations such as schools, sports venues and polling places.
Schedule so people are vaccinated (arrival, to jab, to departure) within the two hour window
Provide assurance that no warrants will be executed nor will persons be picked up by ICE, etc.
i am available to brain storm with you.
Thank you.