For me, the best way to proceed, which I do on Autel Evo and Dji Mavic 2 pro,
1- I turn on the radio
2- I turn on the drone
3- I connect the tablet or smartphone, which launches the Explorer or Litchi application.
4- I am waiting for the Google map to appear in the application.
5- Once the map is displayed, I switch the tablet to Airplane mode.
Even if the application crashes along the way, by reopening it, the map will still be there, even without an external connection. (valid only on Android, since the "apple" does not like Google.