Apple expects to have to use "significantly more air freight" and the air freight is planned to get enough units into the channel in time for the holidays.
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"significantly more air freight" as a charge that would affect the forecast's margins.
Upon further questioning later in the call, Cook explained, "The air freight is not related to the iPhone, so these are unrelated topics," noting that the air freight is planned to get enough units into the channel in time for the holidays.