Taking a small amount of psilocybin truffles and then taking more later, within a relatively short time frame, is known as "redosing." Redosing with psilocybin truffles can potentially increase the duration of the effects, but it is unlikely to produce the same level of intensity as taking the entire dose at once. Here are a few things to consider:
Tolerance: Psilocybin and other psychedelics can induce rapid tolerance, meaning that the effects diminish shortly after ingestion. If you take a small amount initially and then redose, the second dose will have reduced or no additional effects due to the development of tolerance.
Timing: The timing of the redose matters. If you redose too soon after the initial dose, you may experience an elongation of the trip rather than a significant increase in intensity. Redosing after the peak effects have subsided may have a lesser impact compared to redosing during the peak or early stages of the experience.