During construction of the Archer Avenue Line, the Jamaica Avenue elevated line was cut back past 121st Street on April 15, 1985. The Q49 bus, which replaced Jamaica elevated service running from the line's previous terminal of to the line's original terminal at , was extended to 121st Street. Until the opening of the Archer Avenue Line in 1988, J trains alternately terminated at 111th Street and 121st Street, with peak period headways to 121st Street being ten minutes. This temporary service pattern was originally slated to be in effect for six or seven months. Construction on the ramps to Archer Avenue was completed in November 1987, but since the tunnels were not ready for service until 1988, a double crossover east (railroad north) of the station was installed while the ramps were used for storage. The Archer Avenue Line opened on December 11, 1988, and service was extended from 121st Street to .