What is the most efficient way to handle last minute demands affecting the production plan?

The most efficient way to handle last-minute demands affecting the production plan is to firm all planned orders for the replenishment lead time. This approach allows the production planner to stabilize the schedule by making planned orders firm, which means they cannot be easily changed. By using the replenishment lead time, the planner ensures that there will be enough stock on hand to meet the unforeseen demand while maintaining control over the production process.

This method provides the necessary buffer to accommodate sudden changes in demand without significantly disrupting the overall production schedule. Properly setting the replenishment lead time allows for effective response to urgent requirements, ensuring that materials are available when needed.

In contrast, the other options may imply different levels of flexibility and control that may not meet the urgency required for last-minute demands. While setting MRP types and using planning time fences can help in various planning scenarios, they do not directly ensure the immediate availability of stock to meet sudden demands in the same manner that firming planned orders does. Furthermore, utilizing manual firming fences can lead to potential inconsistencies and may not provide the same level of proactive management necessary to handle last-minute changes effectively.