The Canada Border Services Agency announced last November that its hours of service at 35 land ports of entry across Canada as of tomorrow (Jan 6).
Some of those border crossings with changes are in Saskatchewan in Carievale, Estevan, Monchy, Oungre and West Poplar River.
All of them have a few hours cut from their weekly schedules.

According to a CBSA news release, the changes were determined in collaboration with the United States to enhance overall security for both countries, because it allows the CBSA to use its resources more efficiently by deploying officers at busier ports.
The CBSA says almost all of these border crossings are processing an average of two or less vehicles per hour during the hours they will no longer be operation, and travelers have an alternative border crossing within a 100 kilometre radius.

There are no changes to the hours at North Portal.

Carievale
Travellers – 7 days a week:
previous schedule: March to November 8a – 9p, December to March 9a – 10p
new schedule: March to November 8a – 6p, 9a to 7pm remainder of the year

Estevan Highway
Travellers 7 days a week
previous schedule: March to Nov 8a to 9p, Dec to March 9a to 10p
new schedule: March to November 8a to 6p, remainder of the year 9a to 7p

Monchy
Travellers – Monday through Friday
previous schedule: March to end of May 9a to 6p, June to Sept 8a to 9p, mid-September to November 9a to 6, November to mid-March 10a to 7p
new schedule: November to March 10a to 6p, March to November 9a to 5p

Northgate
Travellers – 7 days a week
previous schedule: 8a to 9p March to November, 9a to 10p November through April
new schedule: 8a to 4 pm mid March to November, 9a to 5pm remainder of the year

Oungre
Travellers – 7 days a week
previous schedule: 8a to 9p March to November, 9a to10p remainder of the year
8a to 6p March to November, 9a to 7p remainder of the year

West Poplar River
Travellers – 7 days a week
previous schedule: 9a to 6p mid-March to end of May, 8a to 9p June to mid September, 9a to 6p mid-Sept, to November, 10a to 7p November to March
new schedule: 9a to 5p March to November, 10a to 6p remainder of the year