Virgin Media really need to get a grip on this. It their website, or worse their sales department accept the customer and give an install date, they really ought to be notifying the customer if for some reason installation is then deemed impossible. This is the second thread in a couple of days covering similar non installation issues of cancellation.
If they are saying a survey was carried out then chances are, for some technical reason it can't be installed at the moment. Maybe there isn't enough local capacity in the area