The Lead Time the History Got Wrong
A reorder level is a guess about two things at once: how much you will sell before the next delivery, and how long the delivery will take. The second guess is usually a single number typed years ago. What it takes to work both out from what actually happened, per warehouse, and to correct the history when the history is wrong.
The importer had delivered twice in a row in nine days. Both times it was a favour: a container already in port, a manager who owed the buyer one. The system, reasonably, learned that the importer delivers in nine days. The real figure, by sea, was three weeks. By the time anyone noticed, the reorder level had been calculated on nine days for a month, and the pharmacy chain was out of two antibiotics in four branches.
This is the problem with learning from history: it learns the exceptions too. A lead time that is typed once and never revisited is wrong in the opposite way — it ignores everything that has happened since. Both versions are the single number that lead time ends up being in most systems, and both fail for the same reason: nobody can see what number is in use, or why.
Two guesses, worked out
A warehouse’s minimum and maximum for an item can now be Predictive instead of Fixed. You choose a service level — how likely you want it to be that you do not run out before the next delivery, 95% unless you change it — and how many days of stock each order should cover. AWRA then works out the rest from what that warehouse has actually done.
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Demand
What this warehouse used each day over the last 90 days: approved issues and till sales, less till returns. Days with no sales count too, so an item that sells in bursts is treated as uncertain rather than steady. Optionally, last year’s season adjusts the rate, once there is a year of history, never by more than half or double.
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Lead time
A lead time typed for this item and this supplier comes first. Otherwise, the supplier’s real order-to-receipt days for this item from its ten most recent receipts. Otherwise, the item’s own lead time. How much it varies comes from the same receipts, or from the supplier’s on-time rate.
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Safety stock
Enough to cover both uncertainties — demand that varies and a delivery that varies — at the service level you chose.
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Minimum and maximum
The minimum is the demand expected over the lead time plus the safety stock. The maximum adds the review period’s demand, divided by the supplier’s fill rate, so a supplier who short-ships is ordered more from — never more than double.
Read-only, with the working shown
A predictive level recalculates every night at 03:20 and whenever it is saved. The fields go read-only, and beside them is how the figure was reached. The Reorder screen and stock balancing read it exactly as they read a level you typed, so nothing else has to change. Fixed levels are never recalculated.
When the history is wrong
This is where the antibiotics went wrong, and why the item’s Stock tab now has a Supplier lead times panel. It lists each supplier that has a typed lead time, has supplied the item, or is its preferred supplier, with three numbers side by side: the days you typed, the days actually observed, and how many receipts that observation rests on. Two receipts and nine days is a number you can see is thin. Type 21, and the item’s predictive levels recalculate as you save, not the next night.
History is the best evidence you have, until it is two favours in a row. Then it needs a person who knows better, and a place to write it down.
The same logic is why we keep demand forecasting explainable rather than clever: a figure you cannot inspect is a figure you cannot correct. And it is why the demand side counts till sales — a reorder level that does not hear the till, as the till sells, the reorder point does not hear it put it, is guessing about half its own input.
Three questions about your reorder levels
Where did this branch’s minimum come from?
What you will probably hear
Someone set it when we opened.
How to read it
Then it describes the branch as it was then. Demand and suppliers have both moved since.
What lead time is the system using for this supplier?
What you will probably hear
The one on the item.
How to read it
One number per item cannot tell a supplier who delivers in a week from one who takes a month.
What happens when a supplier only sends 70% of each order?
What you will probably hear
We reorder when it runs low again.
How to read it
A maximum that ignores the fill rate is a maximum you never actually reach.
What AWRA OpsHub does today
- Predictive minimum and maximum per item and warehouse, from that warehouse’s 90-day demand, the supplier’s lead time and its variation, the fill rate and a service level you choose.
- Optional seasonality from last year’s demand, once a year of history exists, kept between half and double.
- Supplier-specific lead times on the item, typed where the history is wrong, with observed days and receipt counts beside them; saving recalculates at once.
- Nightly recalculation at 03:20, with the working shown and fixed levels left untouched.
- The same levels on the web, in the app and through the API, read by Reorder and stock balancing.
More we can add to your workspace
- Lead time per location, so a warehouse far from its suppliers is planned on its own road rather than on the supplier’s single figure.
- Low-stock alerts per warehouse, so a branch manager hears about their own floor.
- Transfer suggestions that fill to the maximum, with surplus measured against the ceiling.
Where we point you to a specialist
- We will not place an order because a level was crossed. The level decides what Reorder suggests; a person decides what is bought.
Lead time per location is the one multi-branch organizations ask for, and it slots into the lead-time order that already exists.
Anything above that you need, we can build for you
Everything listed above as something we can add describes what ships in the standard product today — it is a starting point, not a limit on what AWRA OpsHub can do for your organisation. Kenya's eTIMS integration and its maintained payroll engine are both in the product because clients needed them and commissioned them; neither appeared by itself, and the same door is open for whatever you just read about. One qualification so this is worth what it claims: a small number of things on this blog we deliberately leave to a specialist rather than build — a statutory ledger we will not sign our name to, a rule that would decide a tax question for you, a clinical or member-funds record that belongs in a regulated system — and where that is true the post says so in those words. Everything else is a scope, a timeline and a price.
The operational work, which is what most commissions actually are
An extra approval stage in a chain that does not match the standard one, a custom field set on employees or assets that only your sector needs, an expiry that has to block an order rather than send an email, a report your board asks for in a shape nothing produces, or a scanner or weighbridge feeding the goods-in door. These are the commissions we are asked for most often and the smallest ones we quote — and unlike a revenue-authority pipeline, none of them waits on a regulator.
The module-shaped additions, which are the ones readers ask for most often
A price list with real discount authority, a customer-facing quotation that expires, a bill of materials or recipe costing, a staff advance that is issued, acquitted and chased, a member or unit ledger, a matching rule that holds a payment. Each of these is a build rather than a setting, and each has been quoted before — a bigger piece of work than a custom field, with a written spec and a date instead of a roadmap slide.
The report, document or pack nothing currently produces
The board pack in the shape your board actually asks for, a donor or funder layout, an invoice or receipt template carrying what your regulator or your customer expects, a dataset the report builder cannot reach yet. Usually the fastest thing on this list to deliver, because the data is already in the system.
Systems, rails and hardware you already run
The accounting package, CRM, online store, core banking or custom database you intend to keep — connected through our API so a fact is entered once and appears everywhere it is needed. Plus the physical edge: a scanner, a scale, a weighbridge or a till peripheral feeding the door it belongs to.
How it works: you describe the requirement, we return a written scope, timeline and cost, and once agreed it is built into your environment and maintained as part of the product. Nothing here waits on a regulator or a published specification, which is why operational builds are the ones we quote fastest. Tell us the requirement that would otherwise rule us out — that is a better first conversation than a demo.
Tell us what your operation needsOur position
Work the reorder level out from what each warehouse actually sold and what each supplier actually delivered, show the working, and give a person somewhere to overrule the history when they know better. A typed level stays a typed level; predictive is a choice per warehouse, not a takeover.
See warehouse minimum and maximum levels
Fixed or predictive levels per warehouse, supplier lead times on the item, and a Reorder screen that fills each branch to its own ceiling.
Explore warehouse levelsFrequently asked questions
How does AWRA calculate a predictive reorder level?
From the warehouse’s daily demand over the last 90 days, the supplier’s lead time and how much it varies, and the service level you choose. Safety stock covers both uncertainties; the minimum is lead-time demand plus safety stock, and the maximum adds the review period’s demand divided by the supplier’s fill rate.
Where does the lead time come from?
A lead time typed for the item and supplier comes first. Otherwise AWRA uses the supplier’s real order-to-receipt days for that item from its ten most recent receipts, and after that the lead time on the item.
Will predictive levels overwrite levels I typed?
No. Predictive is a choice per warehouse. A Fixed level is never recalculated; only levels you switch to Predictive are worked out nightly.
What service level should I choose?
Ninety-five per cent is the default and suits most items. A higher figure holds much more safety stock for a small gain, so keep it for items where running out is expensive. Any value from 50% to 99.9% is accepted.
Can I correct a supplier lead time the history got wrong?
Yes. The Supplier lead times panel on the item lists typed days, observed days and the number of receipts behind them. Type the real figure and the item’s predictive levels recalculate when you save.
