According to the MTA:

F Coney Island-bound trains run via the E from Roosevelt Av to 5 Av/53 St

Weekend, 11:15 PM Fri to 5 AM Mon, Feb 28 – Mar 3

Trains resume regular service at 47-50 Sts.

Another reason to stop by and get your No F Train Subway Service door magnets

from the Roosevelt Island Historical Society Visitors Center Kiosk.