SD Availability Check Part 4: Classic Backorder Processing and Rescheduling

📌 KEY POINTS
✅ Backorder processing redistributes ATP among open orders — it does not create supply.
✅ Manual backorder processing (V_RA) lets a planner move confirmed quantities between orders of a material.
✅ Rescheduling (V_V2) rechecks many open orders and redistributes confirmations by a sort sequence (e.g. delivery priority, then order date).
✅ Always run in simulation first and review results; updates change customer promises.
⚠️ Rescheduling without agreed priorities quietly takes confirmations away from important customers.

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▶ WHERE WE ARE
Parts 1–3 covered ATP basics, configuration and scope. Now what to do when supply changes after orders were confirmed.

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▶ 1. WHY BACKORDERS HAPPEN

• Supply delays, stock losses, forecast errors, new priority orders.
• First-come-first-served confirmation doesn't reflect business priorities.

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▶ 2. MANUAL BACKORDER PROCESSING

• V.15 lists backorders; V_RA per material shows requirements and confirmations.
• Planner assigns or withdraws confirmed quantities per order.\n\n━━━━━━━━━━━━━━━━━━━━\n▶ 3. RESCHEDULING (V_V2)\n• Selection: material, plant, date range.
• Sorting: delivery priority (customer master), order date, etc.
• Simulation mode; then update.
• Output: improved/deteriorated confirmations.

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▶ 4. INTEGRATION

• Updated requirements flow to MRP.
• Deliveries already created keep their quantities (reservation via delivery).
• Customer notifications via order confirmation output.

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▶ 5. LIMITS OF CLASSIC BOP

• Sorting options limited; no segmentation by rules.
• S/4HANA aATP BOP (Part 8) adds segments and confirmation strategies.

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▶ STEP BY STEP

1. Create three orders confirming available stock.
2. Reduce supply (e.g. cancel a PO).
3. Run V_V2 in simulation with delivery priority sorting.
4. Review and update; check order confirmations.

✅ CHECKPOINT: the high-priority customer keeps its confirmation after rescheduling.

After a supplier failure, a distributor ran V_V2 in update mode sorted by order date. Several key accounts lost confirmations to small customers whose orders were older. Complaints reached management within a day. The team restored confirmations manually with V_RA, introduced delivery priorities in the customer master, made simulation mandatory with sales approval before update, and later moved to aATP BOP with segments.

• Running rescheduling in update mode without simulation.
• No maintained delivery priorities.
• Expecting BOP to create supply.
• Forgetting to inform customers after reconfirmation.
• Ignoring deliveries already created.

• Agree priorities with sales and supply chain.
• Always simulate and approve before update.
• Maintain delivery priority in customer data.
• Communicate changed confirmations.
• Plan migration to aATP BOP in S/4HANA.

Questions: "What is backorder processing?", "How does rescheduling work?", "How do you protect key customers?"
Strong answer: redistribution of confirmations (not supply); V_RA manual, V_V2 mass with sort rules (delivery priority, date), simulation before update; MRP integration and customer communication; aATP BOP adds segments and strategies.