We are using SonarQube to analyse the code that we checkin to TFS. Every time a developer performs a checkin, the new/changed code is being analysed. This mechanism did well for us, until last friday. All of a sudden SonarQube told as we had thousands of code smells/bugs/vulnerabilities in 1 of our 34 projects. Trying to understand where this came from, I saw a quirk in the SonarQube activities:
- Performing an analysis, SonarQube says 'Quality Profile: Stop using '[x] way'' for 3 quality profiles
- Performing the next analysis, SonarQube says 'Quality Profile: Use '[x] way''
This change in using profiles is also visible in the activity graph:

We made no changes to the quality profiles between these analysis. How SonarQube is being triggered is also not changed in this period. Also, no changes/updates are being made to any of the involving systems between these analysis.
Right now I'm completely in the dark about what have could caused the change in (not) using some quality profiles. My question therefore is: Has anybody encountered this before or can anybody shine a light on where to look for where this came from?