New Build

Has anyone had any experience with connecting Virgin to a new build?
I'm building in my garden and have Virgin Gi1 which comes via a fibre optic cable to the wall between our existing house and the garden. It terminates in the brown box and enters the house using co-axial cable.

When we a finished we will move into the new house and until some time next year Virgin is the only truly fast connection. Next year fibre to premises will go live in the village (has Open Reach fibre to cabinet with the cabinet outside our house)

Not getting a lot of joy from Virgin as my house doesn't yet have an address that exists on their system. It is only up to first floor level as yet so understandable.

Can Virgin connect more than one house hold to the same fibre from the brown box? Does my house need co-ax laying in at first fix? I will be putting in ethernet cabling anyway. (It's a Passiv House so don't want to penetrate the sealed parts of the house after completion and the difficulties of keeping it airtight.

Andy