The oldest lot is not always the right lot to dispatch
For Inventory managers and supply-chain heads · Compare approaches
TL;DR — what you’ll learn
- Calculate remaining life on the customer's expected receipt date, including transit time.
- Separate expiry order from eligibility: released, unreserved stock must also meet the receiving customer's requirement.
- Use a worked allocation to see what changes when a delivery slips.
- Define the exception owner before automating reservations or suggesting alternative customers.
The picker scans the oldest pallet. The order passes a stock check. Two days later, the customer refuses it because too little shelf life remains. Nothing went missing in the warehouse; the allocation rule answered the wrong question. FEFO inventory needs to account for the receiving customer's commitment, not just the date printed on the pallet.
How should FEFO allocation handle different customer shelf-life requirements?
First identify the lots eligible for that customer and delivery date. Then allocate the earliest-expiring eligible stock. A lot can be usable somewhere in the business and still be unsuitable for a particular order.
- 01Read the orderReceipt date and remaining-life requirement
- 02Find eligible lotsRelease, expiry and reservations
- 03Check arrival lifeInclude the planned journeyDoes the lot meet the requirement?YesAllocate the lotNoChoose another eligible lot or route the changed commitment for authorised review.
- 04Allocate the lotRetain the selection evidence
Illustrative information flow. The article explains the evidence, exceptions and responsible decisions. Diagram: NextEdge Labs.
Count the days at the receiving dock
In an illustrative example, delivery is due on 18 October. Lot A expires on 25 October and lot B on 31 October. A customer requiring ten remaining days cannot receive A under a simple calendar-day calculation. B has thirteen days and qualifies, subject to the agreed counting convention and release status. A may suit another order; excluding it here does not mean writing it off.
Microsoft's shelf-life planning documentation uses the customer receipt date when considering sellable-day requirements. That distinction matters when an overnight route becomes a three-day journey. Record whether the business uses requested or confirmed receipt dates and how it treats delivery changes.
Source: Microsoft Learn · Customer sellable days and receipt dates. Reference details
Make exclusion reasons visible
The allocation screen should show available quantity, expiry, quality status, existing reservations and the reason a lot failed eligibility. Otherwise staff may override a correct rejection because it looks like a stock error. Maintain customer-specific requirements with an owner and an effective date; a sales note buried in an email will not reliably reach every picker.
Check the requirement again when a route or delivery date changes. A previously valid reservation may need a different lot. Keep the earlier decision in the order history so the team can explain why the pick changed.
Work the allocation through a partial order
Extend the example to an order for 120 cases. Lot B has 90 physically present, but 30 are reserved for another shipment. Lot C expires on 3 November and has 100 free cases. The available allocation is 60 from B and 60 from C, assuming both meet all other requirements. A screen that shows B's physical quantity as its available quantity will promise thirty cases twice.
Now move receipt from 18 to 22 October. B has nine remaining calendar days, so it no longer satisfies the illustrative ten-day requirement. C still qualifies but covers only 100 cases. The system should expose a twenty-case shortage and the changed reservation. It should not silently keep B, borrow another order's stock or assume the customer has accepted an exception.
| Lot | Free cases | Remaining days | Allocation outcome |
|---|---|---|---|
| B: expires 31 October | 60 | 9 | Excluded for this customer's ten-day rule |
| C: expires 3 November | 100 | 12 | 100 cases eligible |
| Order balance | 20 needed | — | Planner must resolve shortage |
Choose where the check runs
Checking only during sales order entry is too early to catch everything. Check when promising delivery, reserving lots and releasing a pick; run it again when a material delivery detail changes. These checks can share one rule service so sales and warehouse screens do not calculate different answers. The implementation needs to define which stage creates a warning and which stage prevents the next transaction.
A basic ERP configuration may already support the necessary dates and restrictions. An integration is useful when customer commitments sit outside the ERP or delivery estimates change in a transport system. A forecasting model is not a substitute for either connection. Start by locating the missing input, rather than treating every failed allocation as an AI problem.
What to request in a supplier demonstration
Bring an anonymised order with mixed customer requirements and ask the supplier to change the receipt date while you watch. Then reserve part of the same lot for another order and place the remainder on hold. Request the resulting allocation history, including the original and replacement decision. This is a stronger demonstration than watching a warehouse list sort by expiry.
Agree how an authorised commercial exception will be recorded, and who can approve it. Such approval cannot override a quality hold or a product's safety requirements. Keep those responsibilities separate in the workflow and in the permissions shown during the demonstration.
What belongs in an automation pilot?
Start with one product family and the customers whose requirements differ. Run proposed allocations beside the current method before allowing the system to reserve stock. Compare rejected deliveries, manual reallocations and stock left without a feasible customer. AI may help interpret customer documents, but an authorised person must approve the extracted rule before allocation uses it.
Test a delayed vehicle, a partially reserved lot and a hold placed after picking. The useful result is an explainable change to the order, with a named planner handling the exception. A report that merely lists expiry dates will not resolve that decision.
Summary
FEFO works when the business agrees what counts as eligible stock. Expiry order can then choose among valid lots. Customer requirements, delivery changes and quality holds need the same attention as the expiry field; otherwise a technically correct pick can still become a rejected delivery.
What to do next
- Take five recent orders and reconstruct the shelf life each customer would have received.
- Assign ownership of customer requirements and document the date-counting convention.
- Rehearse a delayed delivery and a new quality hold before enabling automatic reservation.
Compare this workflow with your current setup
Share the step that takes the most manual work, the systems involved and the exceptions your team handles. That gives us a concrete starting point for comparing approaches.
Sources and further reading
Sources checked 15 October 2026. The worked examples and software evaluation suggestions are NextEdge Labs’ editorial analysis.
- Shelf life planningMicrosoft Learn · Dynamics 365 Supply Chain Management documentation, accessed October 2026
Product documentation explaining shelf life and customer sellable-day requirements. A software example, not a food safety specification.
Visual credits
AI-generated illustration created for NextEdge Labs; it does not depict a client facility. Workflow diagram by NextEdge Labs. Icons from Lucide (ISC licence).
