When you re-baseline your project plan using the same baseline number you
will lose all previous information in that baseline field including when it
was baselined.
You could potentially use multiple baselines to see previous baselined dates
side by side and you could even create a Gantt that showed different lines
representing multiple baselines. However, the date the baseline was taken
is only visible in the baselining pop up window.
It is custom to use one baseline for the initial planning baseline, another
for each time the project has gone through a re-planning and approval phase
and one that can be used on a weekly basis before accepting updates to the
plan and doing the weekly statusing of the plan.
I would not use too many baselines if your project plan is large as this can
cause performance issues on saves and updates. A baselines stores not just
start and end dates, but time phased work and cost information. If you are
only concerned with start and end dates, you might want to use the interim
plan features instead of a full baseline.
Hope this helps.
Jonathan Sofer
