SD: Forward/Backward Scheduling

From scheduling point of view following dates/time are important:

1. Confirmed delivery date: date on which system confirms good receipt for customer
2. Requested delivery date (RDD): as requested by customer
3. Goods issue date (GI date): date on which goods leaves delivering plant
4. Loading date: at this date picking and packing should be completed and goods are ready for loading.
5. Transportation planning date: at this date we should start arranging transportation.
6. Material availability date (MAD): at this date material is in stock for picking and packing.
7. Order date: at this date customer places order.

Transit time (D23 - difference in RDD and GI date) – Time needed for goods to reach customer. It comes from route
Loading time (D34 – difference in GI date and loading date): Time needed for goods loading. It comes from shipping point
Pick/pack time (D46): Time needed for picking/packing. it comes from shipping point
Lead time (D45): Time required for arranging transportation. It comes from route

System starts from customer RDD and find out MAD and transportation planning date. Delivery must be created on earliest of these dates.

Backward Scheduling:

• If order date is before these dates (both), customer RDD can be confirmed.
• In this case confirmed delivery date and RDD are same
• And as a result a single schedule line is created
  

Forward scheduling:

• If order date is after any one of these dates (MAD and transportation planning date), customer RDD can’t be confirmed.
• In this case system takes order date as base date and calculates confirmed delivery date and this date will be ahead of customer RDD.
• As a result, system will give two schedule lines; one for customer RDD with zero confirm qty and other for new confirmed delivery date with confirmed qty.
  

This is basic info about Forward/Backward Scheduling, if you need more information on this, pls email me or reply via comments.