His hypothesis is that Amazon will ship prime items first, even when the prime order is placed after non-prime orders. Non-prime items won't see similar shippi

His hypothesis is that Amazon will ship prime items first, even when the prime order is placed after non-prime orders. Non-prime items won't see similar shipping priority until near the end of their deadlines. It's to minimize prime-order shipping latency as much as possible. Incenticizing prime is a happy side-effect.