FlyerTalk Forums - View Single Post - Return flight from Canada w/ int'l layover.
Old Apr 22, 2019, 7:43 am
  #2  
Often1
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Join Date: Aug 2010
Location: DCA
Programs: UA US CO AA DL FL
Posts: 50,262
Your flight may arrive into and depart from the same physical terminal, but the YYZ-ATL segment will depart from the transborder area. In order to enter that, you must proceed through Preclearance at YYZ.

For your purposes, there is no logistical way to clear some passengers at YYZ and some at ATL.
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