This site states this specific timeline directly, in more than one place: plan on two to three months of daily use before judging results.
This figure appears in the site's mechanism section, its FAQ, and implicitly in its package-size framing — worth reading that repetition as this site's central, consistent expectation-setting message.
This site is direct that this timeline comes from how Bacopa studies measured their effects — worth reading this as a research-grounded recommendation, not an arbitrary marketing figure.