The T-70 remained in service primarily in a reconnissance role until the end of the war. The Soviets also requested that Britain continue shipping their Valentine tank (which the Soviets considered a light tank)for use in this role as well.
If you are looking for something in widespread use in infantry support it would be the SU-76. This vehicle was the most common AFV used in that role through the later part of the war by the Soviets.