Those days are completely normal
From my experience...I'd say 5-7 months is fairly predictable. Then around 8-10 you have to tweak a little bit again. And from then on it's mostly smooth sailing
The goals of EASY is to get them on a "routine" of eating after sleeping, though this sometimes needs to be tweaked when transitioning or they take short naps. This helps avoid feeding to sleep/snackers and it is soo much easier to read your babies cues.
For example...my SIL said to me a few months ago "how do you know she's hungry if she isn't crying" :lol: :shock: I LOVE E.A.S.Y.