I've been a VM customer for many years and never had a problem with the land line. There is still a BT line physically attached to my house but it is (most certainly) not active.
In fact if the BT line were a fuse, I'd put a match to it and take great delight watching the explosion at the other end - which (I guess) portrays my opinion of this company!
Hope this clarifies.
Cheers and Si thee