Pro updates expire after about six months (the old installer keeps on working).

You're right to want to update--so much has improved since the installer for OS 9.

So, just use the free installer (it's quite good), or if you want to keep supporting the development, get a new Pro subscription.

Cheers--and hang onto the old installer. I think I still have mine for system 7.61. Might be fun for a few of us to see if we can still connect