YOU- will be the source of reliability for you NG system if the SHTF.
1) find out how your pipeline is run and how many others around you are on it. If many are on it then supply will run low quick. Best to have some wood. Or sneak about and shut all the other residential valves-there will be a cap out front of the house.
2) Once you find out how the pipe runs, you will find the local pressure station. If it is big, there is likely a compressor. Most subdivision or neighborhood stations just have a pressure reducing valve set-up. Your best hope is one of these in a 'low use' area.
The pipeline pressure upstream of the reducing valve station runs 4-600psi in a 12-24" pipe for miles. Your house runs on about 2psi maximum on about a 3/4" pipe for a few yards. This means if you are the only user, there is alot of gas in that pipe. Use at will until the pressure runs low. When the pressure runs low, you will have to adjust the PRVs (pressure reducing valves) If you are handy, it is very easy to figure out. If you are sneaky, you can use bino's to get a model # and manufacturer off the local valve (just birdwatching you see) and download a cut sheet and it will have the instructions.
There will be 2 PRVs on the line with a bypass PRV. Reason is because it is a hell of a cut from 600 to 2, so they generally go from 600 to 150 or so and the second will make that cut to 2psi. the gauge upstream of the second PRV reading over 150 tells you that the upstream regulator has failed. These are ultra reliable, so this is unlikely.
Bottom line is this-CCW on the adjustment increases pressure. This is likely where you are going. The adjustment is under a cap on the top of the valve. It is either a standard screwdriver or crescent wrench to adjust. The valve actuator looks like a flying saucer and may be mounted horizontally.