The Reverse Planning app for Business Central includes a Move Demand Date functionality that works out of the box. When a vendor tells you a delivery will be delayed, classic MRP simply suggests moving the supply line back to the original date. Reverse planning does the opposite. It accepts that the supply situation does not get better and calculates which demands you need to move instead.
You run it from the Move Demand Date journal. It calculates the full impact through the low-level code hierarchy, so production orders, sales orders, assembly orders, and transfer orders that depend on a delayed component all get rescheduling suggestions.
When you carry out the actions, the suggestions split into two worksheets. Everything standard MRP journals can handle goes into the planning worksheet as rescheduling lines. Sales order movements go into a separate sales order handling worksheet, because Business Central has no default worksheet for moving sales orders.
The Move Demand Date functionality only creates rescheduling lines. It never creates new supply.
What Move Demand Date does
The idea behind reverse planning is straightforward. Normal MRP planning grabs demands that have no supply and suggests creating new supply orders. Reverse planning does the opposite. When the supply side does not get better, you need to move demand.
The classic example is a vendor calling to say a delivery is delayed. A standard MRP run would just suggest moving the purchase order back to its original date. But that does not solve the real problem. The delay ripples up through everything that uses that component, and you need to push the dependent demands out to match.
Move Demand Date figures out exactly which demands need to move, and by how much, all the way up the product hierarchy.
Items with no supply are skipped
Move Demand Date can only move demands where there is something to move. If an item has no supply, there is nothing to reschedule. These items appear in the calculation as replenishment items, and the functionality leaves them alone.
You can check this on any item using the Graphical Inventory Profile, a small helping tool available for free on AppSource. If you open the profile for an item and see zero inventory with only sales orders and no supply, that item will not be moved. It gets handled in a normal MRP run, where new supply is created.
A worked example of a delayed purchase order
Start with empty journals. The reverse planning worksheet is empty, and the sales order handling journal is empty. When you calculate, you only get the two replenishment items mentioned above, because there is nothing else to move.
Now imagine the vendor calls about item 1155. In the Graphical Inventory Profile for that item, there is one supply: a purchase order on the 12th of May for quantity 35, feeding a production order. The vendor says the delivery will arrive one week later, on the 19th of May.
You open the purchase order, either directly from the Graphical Inventory Profile or from Business Central, and change the receipt date from the 12th to the 19th of May. This is the situation where things do not get better on the purchase side.
When you run the calculation again, Move Demand Date now suggests moving the production order that uses this component. It still skips the two replenishment items in the middle, but it picks up everything affected by the delay. For example, the production order on item 1150 moves from the 14th of May to the 22nd of May, reflecting the one-week delay plus a small adjustment.
The due date setting affects what can be moved
One thing to watch is the due date in the settings. By default it is set to today’s date, and the functionality will not move anything to a date before the due date. If your example seems to push demands far out, for example all the way to the 1st of August, check this setting and adjust it so the calculation produces a sensible result.
Tracing the consequences with View Supply Chain Changes
To understand why a particular line was suggested, use the View Supply Chain Changes action at the top of the worksheet. It shows you the item that triggered the change, the original due date, and the new suggested due date.
In the example, a production order moves from its original due date to the 20th of May rather than the 19th. The 19th falls on a weekend, so a safety lead time pushes it to the next working day.
You can scroll up through the hierarchy to follow the chain. The front top is part of the front wheel assembly, so when you look at the supply chain changes for the front wheel, you can see it is being rescheduled because of the front top above it. This way you can see every consequence of the original delay in one place.
Carrying out actions and where the lines land
If you want to handle everything in one go, set the action message to yes. The two replenishment items are not selected, because there is nothing to move.
Among the selected lines, some are production orders and some are sales orders in the source type. Assembly orders and transfer orders can also appear here. When you carry out the actions, the lines split into two destinations:
- Everything that standard MRP journals can handle goes into the planning worksheet, as rescheduling lines only.
- Sales order movements go into the sales order handling worksheet, because there is no default worksheet for moving sales orders.
The sales order handling worksheet shows the sales order number, line number, item number, and the dates. For example, move it from a date in May to a date in June. The reverse planning worksheet shows the production and other supply orders you recognise, with the original due date and the new due date.
The key point is that Move Demand Date only ever creates rescheduling lines. It never creates new supply.
Try it in your own database
You can try the Move Demand Date functionality in your own database right now, straight after installing the Reverse Planning app. It works out of the box, with no configuration needed to get started.
Q&A
What is the difference between reverse planning and normal MRP?
Normal MRP grabs demands that have no supply and suggests creating new supply. Reverse planning does the opposite. When the supply side does not get better, for example a delayed purchase order, it suggests moving the dependent demands instead of creating new supply.
Does Move Demand Date create new supply orders?
No. Move Demand Date only creates rescheduling lines. It moves existing demands to new dates and never creates new supply.
Why do some items get skipped in the calculation?
Items with no supply cannot be moved, because there is nothing to reschedule. These appear as replenishment items and are left alone. They get handled in a normal MRP run where new supply is created.
Where do the rescheduling lines end up after carrying out actions?
Lines that standard MRP journals can handle go into the planning worksheet. Sales order movements go into a separate sales order handling worksheet, because Business Central has no default worksheet for moving sales orders. Assembly and transfer orders can also appear.
Why might Move Demand Date push demands much further out than expected?
The due date setting controls how far demands can move. By default it is set to today’s date, and the functionality will not move anything to a date before the due date. Adjust this setting if the suggested dates look wrong.
How do I see why a specific line was suggested?
Use the View Supply Chain Changes action at the top of the worksheet. It shows the triggering item, the original due date, and the new suggested due date, and you can scroll up through the hierarchy to follow the chain of consequences.
What tool can I use to inspect an item’s supply and demand?
The Graphical Inventory Profile, a free helping tool on AppSource, shows inventory, supply orders, and sales orders for an item so you can see whether there is anything to move.