If we modify a project status and auto health rules are activated, does the rule takes precedence on the manual change?
Auto Health was designed to be used as an alternative to manual health updates.
The project manager can still update the workspace health status manually, but while the rule exists and any of the trigger conditions for the rule have been met, the health of the workspace will continue to be reset during the regularly scheduled automatic updates.
Please read the help link : http://h.daptiv.com/Help/PPM/J5_help.htm#cshid=adminhelp/auto_health_update.htm
So if your project status meets automatic rules, the status will be modified.
This is the cons of using automatic tools.