That could really use a check on the track map: the can't get to the Manhattan Bridge from 8 Av.
My solution (in essence, 6 Av is closed):
Trains operate in two sections:
.........Bedford Park Bl to 34 St/Herald Sq
.........71/Continental Av to Brighton Beach, via the in Queens and in Manhattan. Replaces the in Queens.
Trains run express between 59 St and Canal St.
No trains between West 4 St and 34 St / Herald Sq. Transfer between sections via the A, C, E, or F.
Trains run via the in both directions between Roosevelt Av and West 4 St.
Trains run to Chambers St. Transfer at Canal St for service for nearby stations.
NEXT
Due to a track condition, 6 Av can only fit 5 tph per track.