It may be interesting to know if a common timeline for all project area's in IBM Collaborative Lifecycle Management tool is possible.
The production level scenario is that a team has Requirements Management (RNDG), Configuration & Change Management (CCM) and Quality management (RQM) activities, using LPA. But the fact is that you have to create separate timeline/iteration schedule for all 3 project areas, and then remember to update all copies whenever you would make a change. This can be of tedious if your development activities demand timelines for all 3 phases to be the same.
Now let me take you through the current behavior of timeline/iteration usage in all 3 components for IBM Collaborative Lifecycle Management (CLM).
Requirements Management using Rational DOORS Next Generation (RNDG) :
There is no support for timelines in RDNG.
RDNG does however have the concept of baselines that can be used to snapshot the state of artifacts, and with the introduction of DNG 6.0, there is now support for configuration management
You might want to take a look here for the new configuration management support: Administering configurations
Configuration & Change Management (CCM) :
Creating timelines, iterations, and iteration types
Rational Quality Manager (RQM) :
Timelines and Iterations in Rational Quality Manager
Currently this is an open RFE that you can track here: Enhancement 172120: Allow a single timeline to be used for the RM, QM, and CCM applications