At the same time, the BRT moved to eliminate remaining operations that required elevated trains to operate under overhead wire. In most cases this meant using third rail on fully grade-separated lines. When third rail was extended on the Canarsie Line it was decided to extend this power mode only as far as the important station at Rockaway Parkway and Glenwood Road. Beyond that point, frequent grade crossings made third rail impractical. This portion of the line was converted to the Canarsie Shuttle using elevated cars in October 1917 and converted to trolley cars on October 18, 1920.