On second thought, do give VOOM a call.
If they allow it, there's a very good chance the billing would be changed and your stb would still be fully activated w/o any lapse in service. I don't think those two groups work very well together. You just might end up with a really good monthly rate from here on out.
that is an interesting issue i am thinking of getting a used voom box people say is a no no the real problem lies in can you REACTIVATE your unit once its deactivated and do they charge anything can you change name/addresses/phone#'s/visa cards without voom saying no (for those who are buying used voom boxes).