I don't think it is set up that way. There is a setting you adjust but doesn't distinguish between town, base, or strats. Just resupply time in general.
It has possibilities though...
Right now though, you can attack a town with lets say, 4 GVs, including troops.
It currently only takes 1 M3 to resupply the entire town on 1 run. No reason to up anything to defend if you can color flag a town in a single run (assuming the strats aren't hit right away).