Travel to Canada on extended B2 visa

[NYCA1ien]

My mother has an approval for the extension of her B2 visa. The I-94 in her passport expired last month.

We are planning a trip by car to Montreal next month. Would my mother have any trouble returning back to the US or will she be fine since she has the new I-94?

[immihelp]

As long as you are returning within less than 30 days, she should not have any problem.