Hope you quickly settle into your new home.
You need to contact the Homemovers team by dialling 150 from a Virgin landline, or 0345 454 1111 from any other phone, but it's best to call at 8am to avoid call queues and they will process the account closure. (They will check their database to see if there is any possibility that they can provide services at your new home. )
If you don't want to be tied up on the phone you might find the online chat messenger service is availlable on the following page
https://www.virginmedia.com/help/moving-home
VM will still charge the early termination fees but will then refund them as long as you give them evidence, within 30 days of cancelling, of you residing at the new property. They will give you the details of where to send the evidence.
The accepted documents showing your new address are :-
bank statement, driving licence, insurance policy, mortgage information, rental agreement or utility bill
The Home movers team will also process the packaging so you can return your equipment. This is generally actioned after the account has closed. You can also return your equipment to a nearby O2 store.