#602 clarify returned status codes

[Lokowandtg]

Description

Document unexpected behavior.

Type of change

• [ X] Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Testing performed?

• [ n/a] Unit tests
• [ n/a] Integration tests
• [ n/a] Acceptance tests

Checklist:

• [ X] This PR is being made against the main branch, or relevant version branch
• [ X] I have made corresponding changes to the documentation
• [ n/a] I have added testing for my changes

If you have any questions, or want to get attention for a PR or issue please reach out on the #logging-and-metrics channel in the cloudfoundry slack

[chombium]

Thanks for this contribution @Lokowandtg and making things clearer.