I don't get the op he's worried about WiFi? And not worried about anything else , so what about his neighbours ? And everything else
Op has no idea how much RF is floating through there heads.....
It's a start though , so in Scotland you can get fined before something happens , otherwise England? Generally nothing happens until something happens , then they check what was and wasn't done
That's difficult, could be cable , Amy of the detectors , bell box , PSU fault and so on
Hence why calling an engineer is quicker , you may have it displayed on keypad what the fault is when it goes off
Just pick any and delete the account details after so it isn't constantly trying to communicate somewhere
Although as GG said use non adt panel , or try
and update firmware
Well the PIR has alarm contacts so you could use them maybe with a relay just to trigger the input on any autodialer , there many cheaper devices which will do the just b for you on eBay
For example
https://www.ebay.co.uk/itm/Alarm-Installer-Auto-Dialler-with-Controllable-Relay-/233783581818?mkcid=16&mkevt=1&_trksid=p2349624.m46890.l49286&mkrid=710-127635-2958-0
They have different versions , but I would recommend a cheap monthly contract SIM , you will kill your credit quick otherwise
Unlikely
Would be interesting though , even with two independent sensors , the shock would suddenly be on access mode provided you can open the door with the shock activation, and or having an over zealous delivery driver come knocking on the door