How do I plan around long supplier lead times?

Push the decision point earlier and reduce what each decision commits. Order in more, smaller tranches with staggered arrival dates, negotiate a partial-release schedule against one purchase order, and hold safety stock sized to lead-time variability rather than to demand. Where possible, split volume across a second supplier with a shorter lead time.

Long lead times make the forecast horizon longer, and forecast error grows with horizon. Every week of lead time you remove improves accuracy without improving the model.

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