Time travel isn’t a supply strategy. Yet many ERPs carry past-due production, purchase, and transfer orders—ghost promises from yesterday. Keeping them doesn’t make you on time; it breaks your ERP, corrodes behavior, and pushes planners to run the business in spreadsheets. Here’s why those zombies need to go—and what to do instead.
Why past-due is poison
A past-due order is an open supply order with a due date earlier than today. Every day it remains late, your system pretends yesterday had infinite capacity and suppliers teleported parts. Cute fiction; ugly consequences.
What it does to your ERP
-
Lies to Sales (bad ATP/CTP): The system treats “due yesterday” as “arriving any minute,” confirming ship dates you can’t meet.
-
Exception overload: MRP spams expedite/overdue messages for the same items; real issues hide in the noise.
-
Hogwarts capacity: Loads stay stuck in closed buckets, so today looks magically underloaded while the shop floor drowns.
-
Inventory whiplash: You overbuy easy parts, underbuy the constraint, and end up with SLOB next to stockouts.
-
Financial mess: Back-dated receipts into closed periods spawn variance soup and auditor eyebrows.
-
KPI distortion: Plan Adherence, OTIF, and DOH are graded against a fantasy plan.
The behavior bomb: why planners abandon the system
Leave past-dues festering and humans do what humans do—they work around them.
Shadow planning cascade
-
Spreadsheet scheduling: Planners copy data out, re-sequence in Excel, and email the shop.
-
Invisible promises: Customer Service commits dates based on side-channels; ERP never heard about it.
-
Double data entry: Some updates make it back to the system…some don’t. Pegging and priorities go stale.
-
Version chaos: Which tab is the truth—“Final_v7_REAL_this_time.xlsx”?
-
Master-data drift: Excel quietly assumes a different lead time, yield, or lot size than ERP; reality diverges.
-
Trust spiral: Sales and Finance stop believing the system, so more workarounds appear. Congratulations—you’ve built a very expensive calendar.
Why this is bad (beyond the grey hairs)
-
No single source of truth: ATP/CTP, procurement, and shop dispatch don’t match—customers notice.
-
Lost traceability & auditability: You can’t reconstruct who decided what, when, or why; compliance risk skyrockets.
-
Worse decisions, slower learning: Spreadsheets kill scenario discipline, assumptions logs, and post-mortems.
-
Cost creep: Expedites and rework hide in email threads, not in variance reports where you can fix root causes.
The right posture: zero past-dues, every day
You can’t deliver in the past. Treat open due dates < today like a quality deviation: not allowed.
The daily “sweep” (five minutes that save your week)
-
Snap to today: Mass-move all open past-due orders to today (or the next valid bucket).
-
Re-plan for reality: Re-run MRP/APS so capacity, materials, and lead times recalc against real dates.
-
Decide, don’t drift: For each order, pick one: reschedule, split (partial now, balance later), or cancel/short (with proper approvals).
-
Refresh ATP/CTP & notify: Update customer commits with real dates.
-
Kill the shadows: If an action isn’t in ERP, it didn’t happen. Ban execution off spreadsheets.
Guardrails that make it stick
-
System rules:
-
Block creating orders with past due dates; enforce reschedule in/out messages.
-
Set planning/firming fences; turn off “infinite capacity” near term.
-
Disallow back-dated postings except via controlled variance workflows.
-
-
Process discipline:
-
Fixed cadence for forecast cut → MRP run → supply publish.
-
A living assumptions log with owners and evidence.
-
-
Exception design:
-
Past-Due Aging dashboard (0–2, 3–7, 8–14, >14 days) with named owners and SLAs.
-
-
RACI & incentives:
-
Supply Chain owns dates; Customer Service owns commits; Finance owns period integrity.
-
Tie leader metrics to plan adherence and past-due aging.
-
-
Shadow-plan amnesty (with teeth):
-
Use spreadsheets for analysis only; decisions must be posted back to ERP within the cycle or they aren’t real.
-
Quick checklist (print-me)
-
☐ Zero open orders dated before today (daily).
-
☐ MRP/APS re-run after the sweep; exceptions worked by owner.
-
☐ ATP/CTP refreshed; customers informed of real dates.
-
☐ Past-due aging reviewed at site/network with actions.
-
☐ “No shadow execution” rule enforced; if it’s not in ERP, it’s not the plan.
Bottom line: Past-due orders are zombie promises that wreck your system and drive planners into spreadsheet wilderness. Kill them daily, keep planning inside the ERP, and let your data—and your people—do their best work in one shared reality.
