Personally I think the "Sky can't take over the TT line" is one of porkies, but the equipment issue at the exchange is probably very real. You shouldn't need to have a 2nd line installed just to move from TT to sky.
Unless you have a good offer from sky I'd say ditch the provision.
Potentially, I know I shouldn't have to have a 2nd line - I declined the offer twice as they kept pushing that as the solution. I think the exec/complaints team have got bored of my issue and struggle to find the root cause.
I was adamant they sort the takeover properly from TalkTalk, but after 4 weeks I've given up and just want to switch. I can't stand TalkTalk's poor network.
To give more context, the original order made on 11th November was progressing OK for a week. Apparently I was going to be put on Sky's new SOGEA network (where the phone goes to VoIP). It fell down after a week, when some idiot at Sky cancelled the original order - after I asked them to put me on the Black Friday deal which should've just been a billing change. Instead they cancelled the order and re-did it entirely.
Ever since that 1st SOGEA order was cancelled, I complained and escalated it to the Exec team - since then they've had every order rejected by Openreach's system. Apparently stating there is still an order pending on my line. We repeated this process 4 times, before they said the only option was to get a 2nd line. From what they explained, there excuse was 'teething issues' between Sky's order platform on the SOGEA product and Openreach's end.
The current chap I'm speaking to reckons TalkTalk have a hold somewhere when the 1st order was cancelled. But I'm not sure whether to believe this or not. He said the proof in the pudding would be when I ask TalkTalk to terminate my service and they hit an issue, as apparently this hold will stop them cancelling the line as well? Who knows........
There is an outside chance that Sky has congestion issues and is waiting on a move from a 1 Gbps handover link to 10 Gbps handover link, but impossible to know from the vague language used.
If it is a VDSL2 cabinet issue then that should show up when looking on https://my.btwholesale.com/includes/adsl/adsl.htm (use Address Checker) enter a postcode and select the correct address from the subsequent list.
I can't give you any more detail than what I've expanded on above, that is the best I've heard from Sky's mouth on the issue.
BT's DSL checker states FTTC and SOGEA availability is 'Available' - not waiting list etc.