10.10. As a Small Business, when should I plan to purchase Distribution Licenses for my product?

As long as you qualify for a Small Business license, you will have a vaiwer for purchasing Qt for Device Creation Distribution Licenses. 

This vaiwer is defined in Qt Developer Framework Exhibit 2, section 6.

If you no longer qualify as a Small Business, all normal licensing terms and conditions as well as prices, including Distribution Licenses, will be applied to your business from the day onwards you ceased to qualify as a Small Business.