I think they need at least a few dozen. They will need to watch their backs. You can’t forge a cadre from 3-4 people, either. I can see rotating a few dozen in and out at a time, though.
It’ll be hard, because no open fires are allowed. I wonder if they will get away w/propane catalytic heaters?
It may come down to their dedication vs. that of the cops. Or zer0’s poll numbers.
A little covert ethyl mercaptan/ethanethiol spill might help....