Without data I couldn't say what caused a shortage or even if that's the cause of the delay. I really have no idea.

Sure, It's possible a supplier just 'ran out'. But in my experience shortages are more often caused by some quality problem which propagated into the supply chain some distance before it was detected, resulting in scrap or recall. It doesn't take much in the complicated world of long outsourced supply chains and Just In Time inventory to cause a major delay. I've seen it many, many times. Just sayin.