Hi mistyben
This sounds very unusual as I would expect that you have a perpetual licence for your Serial Number, regardless of being a Professional Partner. I had been been a Partner up until 2011 when I stopped paying MYOB because I hated the new versions of MYOB and I have continued using my MYOB v19 files (40 in total) ever since, which I confirm when required. I can process clients who are online with their own subscriptions by downloading the new versions but I don't personally need a subscription. It is possible you are being coerced into paying for subscriptions that you don't need but I'm sure a Moderator on here could confirm whether you have to change or not..........
Cheers
Liz