Lag Calculations in Project 2003 vs Project 2000

[Greg]

I recently moved a project from MSP 2000 over to 2003. One of the tasks had
its start date change. Its start date is driven by a FS+lag. How could this
be? Same logic, no progress, start date different. Same project default
calendar.

 

[Steve House [Project MVP]]

Lags are handled the same in both versions. Could something upstream have
changed and that rippled down to cause the change in start date you're
seeing? If a task was scheduled to end, say, at 3pm and its successor was
FS with a 1 week lag, a change in the predecessor's finish from 3pm to 5pm
could cause the successor's start to apparently change by 1 full day. (It's
not really a full day but it will look like it is unless you format the
dates to shown times as well.)