tbh if you actually did get her to sleep a 9hr stretch at 11wks, do not worry about the nighttime feeds. if dd wakes and is hungry, then feed her. but i really see nothing wrong with skipping the df (as long as day ounces are good) and waiting for her to naturally wake....no matter when that may be.
i only tried the df a few times with my dd...it seemed to cause us more trouble than it was worth. by 12wks, my dd would sleep from 7-1am, then feed...and maybe again around 430/5am and back to sleep till 7/730.
really, just find what works for ALL of you.
how does she sleep during the day?
hth
sami