robmar0se wrote on Dec 14
th, 2005 at 4:37pm:
[...] Tried the nnn7 number, unfortunately just a recorded message refering to the 0870 numbers; do you suggest trying all the numbers in the range?
Yes. It's best to do this out of hours for obvious reasons. I suggest you withhold your number with 141.
They've got a handful of 0870/1 numbers (which fax numbers correspond to which NGNs will be more difficult to pinpoint), and even though you're just after one of them, it would be useful to know them all.
I suggest you ring each 0870/1 to see what recording or menu options it answers with. Then ring different DDI numbers listening for that message. If the NGN answers within a couple of rings, you know that the geographical will aswell, although you could hang on to see if it is someone's direct number (ie they have their own voicemail on).
It's worth making a note of what you find on each number, ie if a number is unanswered, out of service, voicemail, fax etc. That way you know what you've done and you may need to refer back to it later.