-Because there is not record about your travel to Canada by using automatic visa revalidation rule, your AP application is OK. As long as USCIS approves your AP, you an use this AP for future travel.
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863211:
Why there is no record of the travel to Canada? When people enter US from Canada, the port officials will re-issue the I-94. They also put information in the computer system. So there is some chance the USCIS will know the travel, is it right?
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