The weeks after
“Integration” gets used loosely, but as a concept in the literature it describes something specific: the ongoing process of making sense of an experience and folding whatever is useful from it into daily life, over time, rather than in one sitting. Analyses of how integration is actually practiced describe it as a process, not an event, and one that keeps going well past the days immediately after.
That matters because a common pattern is a rush of insight or resolve in the first days after an experience, followed by that resolve fading without daily life ever visibly changing. This isn’t evidence that the experience “didn’t work” or that the person did integration wrong. Sudden sweeping resolutions are just hard to sustain by nature, whether they come from a psychedelic experience or anywhere else. Insight and behavior change are related but separate things, and the second one is slower and less dramatic than the first.
What tends to hold up better than a grand resolution is something small and concrete: one specific, ordinary change, repeated, rather than a declared transformation. See One small thing for what that looks like. There is no deadline on any of this, and no requirement that anything change at all — see I had a good time for the other valid outcome.