What's your PSI reading (room temp) after filling from General Fire?
PSI does NOT matter... As long as there is liquid in the tank, the psi will be the same. It will not start dropping until the liquid is all gone and you are just about out of gas. Days, week, maybe hours, depending on tank size, operating pressure, and consumption.
I use linweld in SD, and they fill on the spot if I ask them. Airgas basically NEVER fills on spot, as they use central filling hubs. Unless you go to that hub, but still won't refill same day usually. You can get your tank back ifyou want to leave it for a day or two though.