Never heard of that before, so my previous posts do not apply. Never mind.

Yes, the water heater is in the attic. Her home is near Raleigh NC which I understand is not uncommon in that area. If she turns the water off leading into the house but leaves the gas water heater on in the attic then if she has a leak on the hot water pipe leading out of water heater, I believe gravity will drain the water heater and without water in the tank could cause a fire. I am inclined to advise her not to turn off water into house for this reason. However she has already incurred two water leaks in the house and by leaving the incoming water on while she is away she may run a risk of a mess when she gets back. She can not get access easily into her attic and since it is gas, she does not know how to turn off and later turn on pilot light.

U are CORRECT!

as an old gasman, turn off house water,and set gas valve on pilot,you may have to remove cover to get to the gas valve or you have a new type with a electric switch and aplug in cord,just unplug.if you get a water leak in the piping with water shut off ,tank will still have water in it. but if you get a leak in the hot water tank you could get 40 gals of water below.most attic water heat. have a plastic pan under water heat to catch this water.........hope this helps