can my partner sign up in her name, at the new address, but still pay from the same join account?
Legally, yes. We don't have joint accounts with VM, so she is a new customer at a new address. I wouldn't have thought that the same bank account as you would be a problem (although this is VM we are talking about).
Bear in mind you can't transfer email addresses, you'll have to return all the existing kit and your wife will have to wait on VM to provide kit, and if there's not an existing connection at the new property, you may want to acquaint yourself with posts in the forum about the sometimes months-long delays in getting VM installed when a new cable is needed. I think the record for delays past the originally promised install date is currently over eleven months.
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