API's are backwards compatible. We may add data to outputs but we do it in a way that there should be no issues. If there is an API not working, it would be a bug. Please provide whatever calls you are concerned about and we can take a look. There was a post by Chris which has been overlooked and I stumbled across it when I searched for other concerns. I've asked our team to respond to that thread and we will look at those as well.
Tim Uzzanti
CEO
SmarterTools Inc.
www.smartertools.com