Backscheduling for fixed Leadtime

[hsiao_te_wang]

Hi Lists,
Does someone know the logic/rules how backscheduling works for fixed leadtime items ?
The client insists to use the fixed leadtime for some reasons but I can not find the logic/rules how system work to backschedule the fixed leadtime to have the start date/requested date for each operation.
I tested many times and it seems not relates to F3007 but I can not explain sometimes two consecutive operations share the same date as start/requested date and sometimes did not.
Also noticed the start/requested date for each operation will also affect the loading for that work center after run R3382 to do the capacity analysis (again, it seems not relates to F3007)
It can be more complicated one of the operations is outsourced and the start/requested dates can be more weird. (I found standalone item 2203 pretty close to our items and tried on Demo Jr. still have no conclusions)
Anyone has any thoughts what I faced to ? Thanks for any inputs or comments !
Regards,
John Hsiao, Xe Update 6, SP19.1

 

[Larry_Jones]

John,

Document omn-99-0120 in the Knowledge Garden documents how Fixed Leadtime Backscheduling is "supposed" to work. I say "supposed" because the code involved has been subject to many fixes over the last year or so (look up the SARs on B3100240). I think the Variable Leadtime Backscheduling works pretty well now, but we don't use Fixed Leadtime so I can't tell you if its working right.

Regards,

 

[hsiao_te_wang]

Larry,
Thanks for the comments.
The document mentioned is the only one I can find in KG talking about the backscheduling on fixed leadtime. Unfortunately, the document is totally different with what I tested on fixed leadtime issues.
The variables maybe OK but not for the fixed leadtime, and that is why I posted my issues to Lists for asking help !
John Hsiao, Xe Update 6, SP19.1