Autistic Pride Day

Autistic Pride Day ..., sounds like a day for people with autism who are gay ! Not a good choice of words

I agree with you that maybe they should support it. But their may be reasons we do not know about that means they do not support it. Maybe you could contact them about it?

On 24th June, Autistic Pride Day, is celebrated with events around the world, to persuade “neuro-typicals”, people not on the autism spectrum, that autistic people are “unique individuals” who should not be seen as cases for treatment.  It is a celebration of autism and is designed to counter the notion that autism is a "disability" to be eradicated. The NAS should support this.

I have not heard of this but I know they have Autism Awarness Month (April) which includes autism awarness day (April 2nd) which they do things for. I have never worked out why they need a day and a month both for autism though but I know they do things to raise awarness of Autism in April. 

18 June each year

When is it held?