Hey Eric,
Glad to hear you're enjoying Continuum - thank you for your support.
To answer your question, yes, each BCC Unit is a separate license. If it were me, and I were considering the Warp Unit and already owned a couple of other Units, I'd call in to Boris FX and chat with a sales rep to see about a discounted upgrade into the full product based on the fact that you already have a couple of Unit licenses. You will be told that the money that you have already spent on your current BCC 11 Units is subtracted from the price of the full product. Note that Continuum 2019 is on the cusp of release and a full product purchase of Continuum 11 at this stage automatically entitles you to the Continuum 2019 release.
So ... if you've already spent say $600 on BCC 11 Units and want the full Continuum product then the price for that is reduced from $1000 to $400.
I hope this info helps.
Cheers,
Peter.