I believe in flexible schedules as I think that helps teach babies to differentiate between day and night. During the day I started a basic every 2 to 2 1/2 hours and then let her dictate at night when she wants to wake up. If she wants to feed outside of that schedule I let her but it really didn't take long for her to adapt to the 2 hour schedule. Some days I marvel at her internal clock as she begins to fuss nearly on the minute. I will wake her up for a feed during the day if it's going past the 3 hour mark though.
I had a much stricter schedule with my son but now I'm a bit more relaxed in that regard. I'm trusting she will steady on her own as she gets older. I find schedules help me figure out why she's crying. "Oh, it's been 2 hours, she's probably hungry". My DD tends to skip the early hungry cues and goes straight to screaming. lol
DD is not sleeping through the night yet though she has done 7 hours a few times. We're still trying to find a consistent nighttime routine that will help her settle. We do aim for bedtime to be between 10 and 11. I need a more consistent wake up time but it's so hard to drag my own sorry carcass out of bed. ha ha