What is the function of the NAS?

Government service provider. Nearly 90% of the income for the NAS comes from the government. Almost all of it is ringfenced for individual people and used to pay for NAS run special schools for children who qualify for them or residential care services.

The government funded charity thing is a bit of smoke and mirrors.

They appear on the account sheets as charity support or some such, in order to deflect from the fact these charities are in effect quangos.  The government does not have any say in how they are run, but they are meant to have charitable aims.

The.  trustees cannot benefit financially, but there can be a number of executives who get very rich for their efforts.  And this in effect is where fundraising efforts go - into the pockets of the executives.  Volunteers are usually a great part of the workforce, they get expenses but not payment, and normal employees are often on low wages.

I am stating this as a general point, and it may not apply to any particular government funded charity that you think of....

Is not charity status often used to avoid paying tax to same government? 

This has been set up by an autistic OT: www.autisticempire.com/

This has been set up by an autistic OT: www.autisticempire.com/