Vermont/Quebec crossing times in early June?

Hey y'all! American here. My friend is getting married in early June and for a Bachelor Party, we're going to Montreal for a few days.

We plan to enter Quebec on the I-81 crossing, the St. Armand-Phillipsburg point of entry.

Two days later, we're headed back over, most likely the I-91 crossing, the Derby Line point of entry.

Is anyone here familiar with one or both of these crossings? If so, can you tell me roughly how long to expect the crossing times to be at this time of year? Google tells me that both stations are open 24 hours a day, but if that's somehow wrong any corrections would also be appreciated.

Merci/Thank you!