New Code definition confusion

Has the method to determine what code is new changed in the latest version?

SonarQube gets confused in one of our Go-projects, as it cannot determin what release is being worked on. How does SonarQube determine versions in Golang projects?

I consider changing the New Code setting to a time period. Do I remember correctly that this was 30 days before?

What are the side effects of this (what is the unexpected functional behavior)?