When you start the activation process for a new hub the old one is deactivated first, as only one hub can be active per account. If there was an issue you would need to call VM to get them to reactivate the Hub 3 before you could use it again.
My setup: V6 TV box, M350 Fibre broadband with Hub 3 in modem mode connected to a Netgear R7000 router. Telewest/VM user since 2001.
As a Very Insightful Person, I'm here to share my knowledge. I don't work for Virgin Media.
Thanks for your help. Virginmedia say they have sent the parcel and Yodel know nothing about it so Im not optimistic it’s will arrive on Monday anyway. I’m also not sure I’ll be able to contact virginmedia to wind it back if I have a problem.