Maybe

UI = Update interval (seconds, default 30min):
Cell (default) / Cell+Gps / Gps
GO = How long wait for a coordinate (default 30sec)

if not network, then not update

with cell, always i have a coordinate
with cell+gps, if the gps NOT fix, then fallback to cell
with gps, if the gps NOT fix, then not update

waiting for yours comments...

btw: the qtm location do not work well, never stop the gps, and always use the gps