WFAN announced it would begin airing on 101.9-FM in addition to its longtime home at 660-AM at 12:01 a.m. Friday.
CBS Radio announced the simulcast plan earlier this month but had not previously set a firm date for it to start until Monday.
The added station gives CBS a potential New York outlet for the national sports network that is to begin 24-hour programming Jan. 2, 2013. The company eventually could air national shows on AM and local programming on FM. In recent weeks, WFAN listeners have been hearing the "CBS Sports Minute," an element of the national network.