I had my VM installation today for Broadband and Phone. I also was advised during a Pre-Install Visit by a VM Engineer to request a BBU to be added which is an emergency backup telephone line if we ever have a power cut.
There seems to be some confusion around whether the built in PAYG sim in the BBU requires to be topped up. I have recieved different messages from different VM Engineers. The main need for the BBU is because my Alarm system has a Dialer so in an event it is set off it calls my mobile (and others). Now I understand as with any sim it doesnt need any credit for emergency services to be called - so a little confused why one engineer advised to top up and others have not and there is no instructions in the box or provided.
I am just uncertain why the Pre-Install Engineer advised that it can be used for non-emergency calls by topping up the sim. Also the engineers who attended today to install were under the impression that it did not need to be topped up as it is a service being provided by VM and that they have installed it in houses where it is used for the elderly where it calls a call centre for lifeline support so this suggests it works for non emergency numbers.
It doesn't need a topup, it only works for 999 and 112 calls as stated in the guides. I don't know why you were told that it works for non emergency calls when it doesn't. The way it works it connects to the strongest mobile phone network any network in fact, so even if one of the mobile networks are down it will still work.
I dont work for VirginMedia all opinions are my own. 39 years in IT.