This site's own five-habit list closes with this specific point: give it 30 to 90 days.
This site describes it directly: consistency matters more than any single day — worth reading this as the habit that ties the other four together, since none of them work without sustained follow-through over this window.
Worth noting this site places the timeline habit last, after the more immediately actionable habits — worth reading the order as building from daily actions toward the overall commitment they add up to.