Vapor lock issue?

Air in the filter doesn't matter much, unless a checkvalve in the pump is bad, then the compressed air in there will unload after shut-down and blow the fuel backwards . No big deal if the bowl stays full.
But if the checkvalves are good, then the pressure will hold, and when fuel evaporates from the bowl, and the floatvalve opens, the trapped air will fly up the pipe into the bowl. Eventually, the trapped air will be gone.
Unless new air is coming into the pump......
and the most likely places for that to happen is at the rear jumper, cuz if it was at the front you would see the evidence wherever the fuel is leaking. Only the rear jumper is higher than the fuel level and does not leak fuel.
And remember; the fuel pump does not suck. It creates a low-pressure area in the system. And atmospheric pressure, in the tank, forces the fuel to move towards that low pressure area; in the very same way that you "suck" pop up a straw. Now; if the atmosphere cannot get into your tank, your pump is gonna stall. The fuel will boil in the low pressure area,becoming a lighter than gasoline gas, and it will rise up to the float bowl. Some of it may get trapped in your horizontal filter and "appear" to be air.
So make sure your tank is vented.