Comment by brailsafe

That's a tough one, but considering it's only the 7th major version to come out in 23 years, I'd say that's a fairly safe place to demarcate backwards compatibility, considering that it's (probably) a fairly major UI overhaul on both iOS and Mac. Despite the poor quality of the OSes themselves, it's just a small studio, gotta pick your battles carefully. You can still use the version you're using, and if you ever upgrade to the new OS you can get the new version, seems reasonable enough to me