Hey peoples, i have this question as the title states.

Yesturday i drove to beach with for a flight to test a new battery that was a replacement for a failed one. (thankyou DJI and EE Hobbies Melb).
I suspected the FW would not align with my AC .400 FW. I started the MAvic inside house prior to beach trip and was awaiting FW update indicator and had full wifi.
No update option was given, so to cut it short, when i loaded this battery down at the beach with no sim and no wifi, it wantede FW update for battery. Ok i said and slowly for about 5 minutes it made it to 100% and confirmed update success.
Does this happen over satelite?
I cant figure how else it could have updated and consider the waiting time to long for the FW to be cached.
Anyone know about this topic?

cheers  

The batteries get the update directly from the Mavic

I thought that is how it worked, but the time taken and the percentage bar made me scratch my head.
When i checked indoors, i would not have had satelite reception which sort of added to my line of thinking.

I have never heard of the updates through satelite, just thought id ask. hehe