When there are disruptions to sleeping or feeding, whether caused by illness or teething or reflux or just developmental leaps or growth spurts, EASY kind of goes out the window, at least temporarily if not in the longer term.
If a different routine works for you/him, then by all means go for it. My DD2 had, I swear, a different Sleep schedule Every. Single. Day! for her first two years: she'd wake for the day at different times, nap at different times for different lengths of time, go to sleep at night at different times (despite our best efforts to keep at least THAT constant LOL), and NW at different times for different lengths of time. For that one, well, she slept when she slept and we fit in feeds as best we could around that. LOL With DD1's reflux, it was more EASAES until that was resolved. I'd say to not get too wrapped up in whether you have an "authentic" EASY routine; follow cues for now, make sure he's as comfortable as possible and has enough to eat and enough time to sleep overall, and odds are that something will shift and you'll have a routine that works for you all.