I'm using the asset_tracker app on a custom board and have built 50 of the custom boards. All but one of them start the modem and listen to the LTE receiver for a full minute before choosing a carrier to connect to. One of the boards connects to the same network it was last connected to a few seconds after startup. I've tried lots of combinations of AT commands to try to get the modems to "remember" the last connected network, but short of forcing a connection with an AT+COPS=1,2,"xxxxxxx" command I haven't been able to get the rest of them to connect in under a minute. Does anyone know how to evoke this behavior? We are not sure what we did to make the single unit that connects directly at startup behave this way.