This site's own four-stage timeline covers the first month across two specific stages — worth reading exactly what's claimed for weeks 1-2 and weeks 3-4, and what isn't.
Weeks 1-2 are tied to calmer focus, and weeks 3-4 to steadier energy — per this site's own stage labels, worth noting that memory-specific benefits are explicitly placed in month 2, not the first month.
Expecting memory improvements within the first month would be reading past what this site itself claims — worth calibrating your own first-month expectations to focus and energy specifically, per this site's own stated timeline.