This is a reasonable request, but unfortunately they don't make use of the direct connect (using the Grill as an access point) to download firmware to the grills. They only use the direct connect to provision, pass your home WiFi information to the grill, and from then on, the grill is independently connected to the network, regardless of your app status.
Their latest version of the software with cloud support is supposed to improve the timeliness of alerts from the grill and it seems to be the case.
But for now, everyone who's grill is not on their home WiFi network must get that fixed before the grill can get updates from Traeger. My Timberline 850 did allow a reset back to original 1.6 firmware and I was able to get it on line and from there it updated to 2.0 and works with the latest version of the app in iOS for me.