Me
As far as membership, you have no choice. That is what you are buying, not software. The software is provided as part of membership.
I didn't write that very well.
The way it works is... you're buying a membership. Your membership entitles you to use the core software as well as other things like the additional content and soft synths etc. Everything that you get now plus anything else they choose to include.
If you buy a new membership and pay upfront (like you always had to) you get to keep the software for ever.
If you upgrade from an old version by paying upfront (like you always had to) you get to keep the software forever.
If you buy or upgrade by paying monthly... once you paid 12 consecutive payments you get to keep the software forever. If you stop the monthly payments BEFORE this, the software reverts to demo mode BUT any software you have already completed payment for (12 months) will still work as it did.
The membership period lasts for 12 months (or monthly) and needs to be renewed to continue to receive updates and new content.