Maybe they are delaying shipping intentionally to make people buy the prime membership.
was it from Amazon themselves, or a third party selling through their 'marketplace'? Either way it's rubbish service.
but I get really irritated when I wait for a parcel that doesn't appear when I expect it, or worse it shows up in the 5 seconds I happen to be in the loo, or otherwise engaged, and all I get is a piece of card telling me to collect me goodies from the post office "TOMORROW" !!!!