If my software is in version 1.0.10, can I delete the files named "***to.1.0.9.wyu"?Answered

Since I'm not sure how WyBuild works, I've kept all the wyu that are on my FTP until now, but I'm beginning to have disk space issues.

Say all my customers are in 1.0.10. Can I delete all the wyu files that are related to previous versions, or do they still have a use?

Thank you