I'm kinda in similar boat like you.
I bought 3 licenses of All-Access subscription at November 2018 and I never used 2018 or 2019.x octane for any project so far (2018 was beta until recently and as you say 2019 is alpha) so i ended up using 4.x for all my projects since November last year so basically i spend 537 USD (there was black Friday discount) + TAX for something i can only start using as of recently (v2018 not v2019 which is still heavy alpha).
So most of that subscription turned out to be for v4 (that was stable production ready build while 2018 was in beta/rc for long time this year).
So i proposed even back then to give us Permanent license option and not force users to subscription only mode (that's not even subscription that's pure rental since software stops working after you stop paying).
sadly i got only 36 votes for that Feature request (that FR system is buried on OTOY WEB that most of people don't even know it's there)https://render.otoy.com/requests/?qa=43 ... w=436#q436
Also back then in November 2018 there was no Octane 2018 plugins for DCC apps until January 2019 so I'd say subscription shouldn't be counted/star until 2018 octane was ready at least in RC phase since they advise NOT to use Bet ain production and yet subscription time expires anyway, totally unfair to users
So for me there should be 4 license options:
1. Subscription/Rent only (like now All-Access)
2. Perpetual for single DCC app (i don't need 20 plugins i need only 1 or tops 2 in my pipeline and I'm glad to pay plugins separately when i need them just like up to v4)
3. Rent to Own (similar like maintenance, you pay for 12 months in advance but you get to keep permanently last version released up to that time (just like some other software companies offer that option)
4. free tier or how they call that 1 GPU mode/version (I'm not interested in that 'coz i believe DEVs need to get their hard earned cash/checks but they obviously want to have free version so I'm fine with that (with some 1GPU limit or so) but don't make "free" version on expense of your loyal customers forcing them in rental only
So Please Otoy give us at least "Rent to Own" if not regular perpetual license for single plugin/Dcc app.