The license is fully transferable as long as the first car is reflashed back to stock. At that point it is transferred back onto the cable and works just like a new one, except that no free tunes are provided.
Also etunes are NOT $50 from Uprev.
The $50 etunes are for updates to a tune that they have already done, for example Osiris standard customers who want additional etunes. If you do not have a tune from them you have to purchase a base tune for $250 which includes 3 etune updates.
Osiris - Base Tune
There are other options for etuning, feel free to PM me if interested.