[Community] Surveillance resistance

[Nick]

I recently stumbled across this:
https://anonfiles.com/file/ec986164e2bb468db76871a6c72caeed

It's a user guide for some hacked samsung phone, and it has several 
rather interesting counter-surveillance features. I imagine some of 
these will be illegal in many jurisdictions ("random IMEI mode" for 
example), but many wouldn't be, and they're rather interesting.

The ideas here that interest me most are alerts when encryption is 
downgraded / disabled, and when unusual numbers of GSM 
re-registration requests are seen. Is this sort of thing possible 
with the GTA04, or is that stuff done at the modem level and not 
easy to determine?

Nick