[DamnMachine]

Resolution of this, in case anyone's interested.
An engineer visited. Signal levels were off, and Superhub was fried, most likely caused by a surge during the power cut.

Virgin told me I was down because of an area wide outage, but that turned to be untrue.

Three of the people I dealt with at Virgin were absolutely brilliant about this, couldn't have been more helpful.

But the Virgin process to provide information and support customers was quite pathetic.
In the end we had no broadband for 8 days.