The Functional Source License says "A Competing Use means making the Software available to others in a commercial product or service that: 1) substitutes for t

The Functional Source License says "A Competing Use means making the Software available to others in a commercial product or service that: 1) substitutes for the Software; 2) substitutes for any other product or service we offer using the Software that exists as of the date we make the Software available; 3) or offers the same or substantially similar functionality as the Software." So if you haven't started your business yet when you make the release, the second criteria wouldn't have any effect. Once you start your business, any release you make after that point would have that restriction. If you change your business, only releases made after you change your business would be restricted in regards tot he new business, and releases made prior would be restricted in regards to your prior business. Honestly, its a lot to keep track of for a user, and a lot of risk, I would always prefer open source alternatives.