I've licensed a piece of software under the Creative Commons Attribution-ShareAlike 4.0 International Public License, but I may not want to allow others to use it for commercial uses in the future, so I'm asking whether or not I can change the license for future versions of the piece of software to other licenses such as the CC-Attribution-NonCommercial 4.0 International Public license.
Unless you've expressly given away ownership (work for hire, signed an agreement with an organization) you own anything you create. Licenses are there to control how you share that code. The code's owner is free to change the terms of how they share the code at any given time.
As a matter of practicality, and to avoid confusion, I would recommend:
- Changing the version number with the change in license--whether there is any material difference in the project or not.
- Provide ample warning to your users that you are doing this change.
If you haven't even released the code at all, then it is as if you haven't picked a license to begin with.