That's a really smart question - I've seen this exact scenario cripple production lines! When your AB ControlLogix supplier suddenly announces a 6-month lead time, the hidden costs of just-in-time inventory can be brutal. You're not just looking at the obvious downtime costs - there are several layers of pain:

1. Emergency premium costs: You'll pay 2-3x normal prices to source from alternative suppliers or gray market channels
2. Production line shutdowns: Even a few hours of downtime can cost thousands in lost production
3. Expedited shipping fees: Overnight shipping from wherever you can find parts
4. Labor costs: Maintenance teams sitting idle or working overtime to install parts when they finally arrive
5. Customer penalties: Missed delivery deadlines and contract penalties

What actually works in practice:

• Dual sourcing: Identify at least 2-3 reliable suppliers for critical ControlLogix components
• Safety stock for critical parts: Keep a small buffer of your most failure-prone modules
• Local authorized distributors: Build relationships with regional Rockwell distributors who might have inventory
• Refurbished/remanufactured parts: Certified refurbished ControlLogix components can be 30-50% cheaper with much shorter lead times
• Cross-training on alternative platforms: Sometimes you can temporarily substitute with compatible modules from other manufacturers
• Consignment inventory: Work with suppliers who will stock critical parts at your facility but only charge you when used

The key is balancing inventory costs against the risk of production stoppages. Most successful operations I've seen maintain a hybrid approach - JIT for common parts, but strategic safety stock for mission-critical ControlLogix components that have long lead times or single-source dependencies.