Air pocket has NOTHING to do with you lack of HOT water FLOW
Water is being heated (electric/propane) and is available
Open a faucet and water pump runs causing hot water to flow out of water heater tank REGARDLESS f air pocket or no air pocket (air pocket is for control of pressure increase due to water swelling when heated---that is all it is for)
Water coming out hot then turning luke warm....
*COLD water has to be mixing with hot
**Cold water can mix with hot thru water heater bypass valve (open or leaking thru)
***Cold water can mix with hot thru inside/outside showers not being turned off using cold/hot knobs
*****Cold water can mix/dilute hot IF cold water inlet DIP tube has fallen off and cold water is no longer being directed DOWNWARD. (pointed down cold water creates a thermo barrier that pushes hotter water up/out.-----it not directed downward cold water can 'stream' upward and heavily cool the hot resulting in warm coming out)
This is an Atwood.........Suburban also uses 'dip tubes'
Need to look inside via drain hole or electric heat element opening etc and see if dip tubes are still in place