Hos does licensing work?

[circle110]

Hi,
One more question before we decide to purchase:

We are considering having a service convert our Yahoo Groups message history into vBulletin's database. They would need to install the software on their system temporarily to do the conversion. Then, once they are done, they would no longer need the software and we would then install it on our server, substituting the populated MySQL db for the empty one.

Is there a way that they could temporarily authorize the license and then de-authorize it so that we could authorize our install? We have no intent to pull any kind of a fast one on vBulletin, it is just that this service would help us immensely and we want to be sure that we can do it with one copy of the software.