Im gonna say it's the short-turning somewhere south of Franklin, (5)s turning at Franklin itself, or less likely the turning at Franklin Ave for the below reasons
- late night GO lists transfers to the at 59th and 168th, implying the is not turning anywhere between Times Sq and Dyckman
-Out of system transfer under the GO lists the and at Rector, implying and to South Ferry, thus it cannot be Wall St switch being used
- is running normal above 14th, is running its full route with extension to new lots