from 3:00 p.m. to 7:00 p.m. Express service was also provided on Saturdays between 6:30 a.m. and 4:00 p.m.. During rush hours, GG trains were extended to Continental Avenue from Queens Plaza, taking over the local. During non-rush hours local service was provided by EE trains which operated between 169th Street and Church Avenue in Brooklyn. The sections of the line east of Roosevelt Avenue were built by the Public Works Administration. This extension was celebrated with a ribbon-cutting ceremony at the Parsons Boulevard station and with a parade along Hillside Avenue. The initial headway for express service was between three and five minutes. 23rd Street–Ely Avenue station opened as an in-fill station on August 28, 1939. Upon its extension into Jamaica, the line drew Manhattan-bound passengers away from the nearby BMT Jamaica Line subway and the Long Island Rail Road. From April 30, 1939 to October 1940, the Queens Boulevard Line served the 1939 New York World's Fair via the World's Fair Railroad. The World's Fair line ran via a connection through the Jamaica Yard and through Flushing Meadows–Corona Park along the current right-of-way of the Van Wyck Expressway. The 1939 World's Fair was served by GG trains, some of which were marked as S Special. Trains were extended to the World's Fair Station at all times during the fair, supplemented by PM hour trains. The fair closed on October 28, 1940, and was demolished later that year. As a result, GG service was truncated to Forest Hills–71st Avenue. After calls from public officials such as Queens Borough President George Harvey to make the line a permanent connection to Flushing and northern Queens, the line was demolished in 1941. After LaGuardia Airport opened on February 21, 1940, the Roosevelt Avenue station became an important transfer point to buses to the airport, including the privately-owned Q33. On December 15, 1940, trains began running via the newly opened IND Sixth Avenue Line, also running express west of 71st–Continental Avenues. 169th Street and Parsons Boulevard were both used as terminal stations during this time, with the E terminating at one station and the F at the other. This setup was instituted to prevent congestion at both stations. New terminal The existing 169th Street station provided an unsatisfactory terminal setup for a four track line, and this required the turning of F trains at Parsons Boulevard, and no storage facilities were provided at