The document provides updates on construction activities for the 91 Project in Riverside County including: - Upcoming full closures of highways and roads like the 91 freeway, Grand Blvd., and Serfas Club undercrossing between April and May for construction work. - Estimates that 1/3 of on-ramps and off-ramps will be completed by the end of spring, 1/3 by the end of summer, and 1/3 by the end of the year. - Details on projects like the widening of the Lincoln Avenue bridge, completion of the Maple Street flyover ramp in July, and installation of tolling signs for express lanes on the 91 freeway.