Re: Mobile as the emergency option?
You do get location from a mobile - if it is using AML and requires certain phone OS's (need to have IOS 11.3, Android 9) at the moment. However, the control rooms also get a triangulation data from the mobile network masts (cells) your phone is registered on - this is accurate to 100m ellipse in built up areas but less in rural - depends on the density of mobile cells.
From the POTS perspective the control room gets the subscribers address details (via EISEC data base lookup) - which comes in very handy for premises aware / risk based mobilisation i.e. nice for them to know in a fire emergency that you live next door to the local petrol station, or live in a flat above a welders, are an old folks home etc. Can't quite see how that works in the future (unless we all have a premises specific IPv6 address and BT re-create the EISEC data base from it).