There's always plenty of complaints for bad service (including from me) so here's something positive.
We're moving in with family while we wait for a new build and we have a few weeks left on a 12 month contract. I called Vodafone and was put through to a "cancellation specialist" who very quickly and efficiently cancelled our plan with no termination fee, then sorted out a better plan at a good price for our new address.
So well done Vodafone.