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Red bars in "work breakdown and schedule" view in formal planning (rtc 4.0)

Accepted answer

It is the Critical Path of the plan.. which may depend on various factors like
- Plan dates
- Work item estimates
- Constraints
- Dependencies
- Project area work environment
-
For work items without an assigned resource:
- Project-level settings, such as working time per day, quitting time, and absences
-
For work items with an assigned resource:
- Resource calendar
- Availability, including scheduled time, absences, and project allocation
Comments

it would REALLY be useful if that was stated somewhere.............:-)

Hello Ross,
Here is the link
https://jazz.net/library/article/657
Look Under Critical Path section
Hope this helps
Regards
Vishnu