In recent years, increasing attention has been devoted to the phenomenon of autism diagnosis in adolescence and adulthood . Waiting lists for assessment have grown rapidly. In England, for example, the average waiting time for an autism diagnosis reached 300 days , substantially exceeding the 91-day target recommended by NICE (Fagg & Woodhead 2023). The rising demand for assessment reflects a broader shift in public awareness and clinical practice. Public discussion often pre

Autism has long been described as a lifelong neurodevelopmental disorder/condition. Core behavioural features, typically emerging in infancy or early childhood, have been assumed to persist throughout the lifespan. The research, however, suggests that within the vast heterogeneity of autism , not all individuals follow a single, fixed trajectory. Various reports have documented the presentation of " acquired autism " ( regression ) following a period of typical development.