The issue seems to have been resolved and the line is finally allowing us to dial outgoing calls again. Just for others which have had a similar issue; sky did their various software resets and the issue was still occurring... we had to contact them to get the update and after a lot of messing about last night (things which just weren't needed to be done again such as checking with alternative phones even though this was done on day one and moving the furniture again since we did it for the Openreach engineer in advance to make it more accessible which basically involved moving sofa's and living room furniture twice which was excessive to actually take a nonsensical photo of a standard Openreach socket with a microfilter attached despite it obviously being confirmed to be an outside line issue by Openreach and their diagnostic machine and confirmed our issue with the inability to register a key press on their machine and our phone) they then re-escallated it back to Openreach to investigate the outside line/exchange etc. and we've not actually been officially updated or contacted since but checked the phone today (as we have every day) and it's now working. Will obvious have to check it's stable and working for awhile to be 100% sure but seems to be responding fine now.
Hopefully more information to follow as to what the fault ended up being but seems like it's most likely between the sky software resets and something to do with the exchange.
