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From August onwards I'll be living in Canada under the WHP program, since I'll be close to the American border I would like to take multiple day (or longer trips, not longer than a week though) throughout the year. I read about entering the country by air on a ESTA and the "90 day" rule that starts when you enter America but also keeps going even if you're back in Canada.
However, I'm wondering if the same rules apply when you enter by land on the I-94 visa? Are the rules the same for this or can I enter throughout the year on a I-94 visa?