There is overwhelming evidence to suggest that intervening early has HUGE benefits:

Potential neurodevelopmental stages of schizophrenia

Psychosis is non-linear. Those in Stage 1 are not pre-determined to move to Stage 2, especially with early intervention.

Duration of Untreated Psychosis (DUP) Versus Rate of Relapse

Research shows that the duration of time in which a person fails to enter treatment has a direct and significant impact upon future hospitalizations. The chart below shows that delaying entry into treatment by one year doubles ones chances of relapsing in the next year.