But more context for you, I went nhs for a diagnosis (adhd) and switched to Right to Choose after waiting a year. Estimate is half year till diagnosis now, not that I trust that though. Mental health services suck in the UK for a reason, a nefarious one, to slowly privatize the whole of UK healthcare. Look at dentistry as example, impossible to get a nhs dentist.

If you think it's important (and also check for ADHD), you can fly elsewhere and do it in an afternoon/very cheaply. I went to Taiwan (quite near to where I live despite being from the UK) and was assessed/diagnosed with ADHD, given a week-long prescription for Ritalin, and Bob's your uncle. Check other countries which may be quicker and cheaper. I booked the appointment a week in advance, arrived, and got it all done in the morning.