from my experience if you keep feeding at 5am, then she will keep waking at that time, when I delayed our early feed until after breakfast I started getting longer sleeps. By about the age of 6-9mo their digestive system can often trigger them to wake up about 30mins before they are used to getting the next food/milk & so that is when they learn to wake up... as you have dropped night feeds you are now "timing" her body for a 5am wake up if you keep feeding.
I'd try holding off with doing something else until the time you want it to be & if you can change the feeding to after solid breakfast