If all you need is your phone number. Go to Tescos get a cheap 2 phone. Plug it in.
Ring 17070 on the phone and have a pen ready...if the line is STOPPED you will get a dial tone but you cant call out.

If you get a 'circuit number' from a nice recorded lady write it down....it's your phone number. You dont have to have the line switched on to find this out.

Give the number to Sky....and see what they say.