Need some help - going on a trip Thursday (well maybe)

My water heater is a gas/electric, although the electric is 12 volts.

The electric is quite fast so I rarely use the gas. We do not boondock.

My water heat came preset at the factory and it is hot hot hot. At times it will bleed off through the pop-it valve.

Fortunately it is also very well insulated so I can run it for 20 minute in the morning and I am set for the rest of the day. We fire it up again for dishes and we are set through the evening.

I do wish it was not preset at the factory.