Following a massive series of failings on behalf of CAMHS, my daughter was only given a formal diagnosis of ASD at the age of 17 years and 11 months, despite me raising the issue with them about 5 years previously. They did not believe that anyone could 'mask' so accurately and also did not believe me when I described the meltdowns which she had at home because she was quiet at school / in CAMHS sessions. She did not get any state benefits relating to her condition during her childhood (a condition which she had, it was just not diagnosed). We are about to try and claim PIP for her now as an adult. But would she be entitled to any backpayment? Thank you