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Delay between End of an Auction and the API GetItem and GetSellerList calls.
It is recommended that your application not rely on the information retrieved from GetItem or GetSellerList until 30 minutes past the scheduled ending time of an auction. After an auction completes, a batch job is kicked off to finalize the relevant database records. In certain high load situations, this may result in a significant delay. In a vast majority of transactions, the time will actually be quite small, but to avoid missing a transaction, the 30 minute buffer period is recommended.