I see that buying the Standard (non-subscription) version of Parallels 17 states that "Free upgrade to latest version" is not available. What exactly does this mean? Does it mean that when a 'bug-fix' up-issue of P17 comes out I will not be able to get it? Or will it simply mean that I wouldn't get a free upgrade to Parallels 18? Or something else? I'm no fan of subscription software, especially something that I use as intermittently as Parallels. But I do need to feel that performance issues within the version that I DO buy will be resolved without continually having to pay for them.