Use 24v Batteries to run 12v System... Possible?

Your idea is correct, many people run multiple 6v batteries in, a 12v bank
But 335 amphrs at 10 amps is 33 hours
So you could camp for the week end , (2) nights, then recharge the batteries at home, on shore power,

can't put that back with two hours of generator run time
Solar of course will return part of your nightly use