New carpool lane hours are coming next month to Highway 101 in Sonoma and Marin counties, Caltrans announced Wednesday. The update follows a previous, highly unpopular change to HOV hours in September, which contributed to congestion and delays through parts of Highway 101. Prior to September, carpool hours in Marin were 6:30 to 8:30 a.m. in the southbound lanes and 4:30 to 7 p.m. for the northbound lanes. In Sonoma County, the hours were 7 to 9 a.m. and 3 to 6:30 p.m. in both directions. The shift in HOV hours was met with sharp and wide criticism, from motorists and numerous lawmakers in Sonoma and Marin counties.