Backward Re-Scheduling - DS Board

[former_member305045]

Hi ,

We have a scenario were we have shortage(demands on 06.07.2016) within the planning time fence (5 days) and when we run PP heuristics we can see that the planned orders start within the PTF and are available on 11.07.2016 with PP firmed indicator (creating an overload).

In DS board there is a fixing interval of 2 days (until 08.07.2016) and there are sufficient slots available to schedule the orders after the 8th. Now when we run backward re-scheduling with earliest date in DS strategy the orders are re-scheduled only from 10.06.2016 leaving out the slot between the 8th and 9th empty, if we run the rescheduling with forward and earliest date in DS strategy the orders are scheduled right after 08.07.2016, utilizing all the slots.

We expect that when we run backward scheduling the orders should utilize all the slots after the fixing interval as the demands lie in the past.

Please help understanding the behavior.

Thanks,

Rajan,

[Sasi2005 · Accepted solution]

Hi Raja,

As per standard SAP settings that I am aware of when you select the "Desired Date" as "Earliest Date", the only dependent combination that will work is "Forward" and not the "Backward and Reverse". The only logical reason that I can understand is when you select the "Earliest Date", which means current and in the future. The main difference between "Forward" and "Backward" rescheduling is in case of "Forward", the Desired date is "Start Date" where as in "Backward" the desired date is taken as "End date". This is the main reason why I feel  when you are trying to reschedule the with the "Earliest Date", option with Forward it starts from 8th where as for backward and reverse it is giving as 10th.

Regards

Sasi

[kenneth_snyder · Accepted solution]

sasibhushan

Can you explain why with backward it is scheduled on 10th versus 8th when using forward?

The demand is in the past so the desired date should be today as you can't create orders in the past.

Can I ask a stupid question:  What is difference between "Backwards" and "Backwards + Reverse"? 

If I select Backwards only , I would think the system would simply "Skip" the demand in the past?

[renato_parise · Accepted solution]

Kenneth,

In any strategy, is possible create orders in the past if you fill "Scheduling offset" field as a negative number.

[former_member305045 · Accepted solution]

Hi ,

The demands are on the 06th and since there is a fixing interval of 2 days , I would expect when I reschedule it should schedule as close to the demands as possible i.e., on the 8th (since there are slots available).

The DS strategy has only forward and backward for rescheduling.

As you can see there is an overload:(Demands are on the 11th), planned orders are available on the 15th as there is a planning time fence

DS Strategy : Backward

Result:Backward Re-scheduling

Result: Forward Re-scheduling

Please shed some light on this .

Thanks,

Rajan

[former_member305045]

Hi Experts,

Please help me understand the behavior.

Thanks,

Rajan.

[tiago_furlanetto]

Hi Raja,

What function/heuristic are you executing? Could you please take a screenshot of the strategy settings?

Regards,

Tiago