Brian
And we explicitly designed it so that you can do this. And for that reason, we've also explicitly made sure that you can see if there are updates availalbe and the changelogs that have always been there for modules that you haven't renewed. We've tried to keep it as transparent as possible so that you can choose if you want/need the new updates.
And this tends to continue to be the case with many business still today. We of course love to see cusotmers benefitting from the continued development that we do on the project and the way we try to do that is to continue to do new great things that will become a carrot for these business owners to adopt the new free versions of the core project, but we are well aware that many PBX's end up untouched for months/years once setup...
As mentioned in the blog, none of this is new. Anyone who has ever purchased a commerical license has had access to the EULA associated with it which has alwasy indicated a renewal fee, which is thought out and based on realistic estimates of what it takes to maintain and continue evolving them. In some cases, such as End Point Manager, the renewal fee only subsidizes the cost, it doesn't cover it at all, since a module like EPM involves full time engineering to keep up with a continously evolving collection of dozens of providers and hundreds of endpoints.
I hope that clarifies some of your concerns. As far as Zulu, it has a differenet licensing model. The pre-release purhcase you made would normally be limitted to 20 seats but the promotion you purchased was for unlimited seats. The licensing terms as far as renewals will be based on the date it actually releases as if you had purchased it that date, so you will get the benefit of the unlimitted seats but as if you purchased it when it comes out.