No I didn't. When I moved to talk talk , which was LLU, they carried out the change over at the exchange so I am pretty sure that the original wiring is still there.
The problem is when you moved your line to TalkTalk, the BT OpenReach wires are no longer connected to BTretail/wholesale equipment at the exchange.
When you then moved your number to VM, they took the number from TalkTalk but installed their own wiring, and the BT OpenReach service was terminated.
Now you want to go to Sky, you need the original BT OpenReach wires reconnecting, and Sky should be able to do that but they might charge (as OpenReach will charge Sky but they might not pass this through). This will connect the BT OpenReach wires to Sky's LLU equipment.
You shouldn't need to have a BTretail service to move to Sky - but in doing this "Sky" will need to be told you have no BT line already. (as you're not paying anyone line rental for those wires).
pro - on THFB - sync about 17.2mbps - BQM