Re: Are the people affected told?
"I guess there's loads of places they could get mobile numbers from though."
Given the "take up" of mobile phones, over the last 10+ years, it's fairly easy to set up an auto-dialler to work through a range of numbers all starting 07...as so many have been issued, there's a good chance of them being successful and hence any numbers that are "live" will give a connection (even if it's just voicemail), while "inactive" numbers won't connect.
So, the issue of "cold-calling" is just down to the probability of the number being "active", as it is with landline numbers.
But the scammers have moved on now and want more than just phone numbers - so a name or part of an address is more useful to them :-(