Scheduling Inconsistencies

We have been experiencing some inconsistent behaviors when we reschedule jobs.

If we have hours in the previous week that we need to reschedule for and want to bring this time in for this week

We reschedule it, shows a start date of 12/17/08, due date of 1/14/09, and a required date of 2/16/09-We backwards schedule. Being that we don't want to have something ready to be shipped out a month before the ship date we then reschedule again.

This time we get a Starte date of 1/27/07 (which is the date that we were resheduling the job) Not sure if that has any significance, a required by date of 2/16/09 and a due date of 2/17/09-which now has the job being finished late.

what we do now is add some wait time operations and reschedule again and things are fine, but there is a lot of tweeking around and manually adding operations to not have this happen, and it takes us three times to schedule the job before the dates are correct.

Has anyone else experienced this and/or have a way to work around this?

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