The area of benefits is certainly a complex one and one that you want to make sure you get the correct advice on.
In my opinion someone like your local Citizens Advice is an excellent place to start, as they will definitely have someone who can give specialised benefit advice. Just remember to tell them you are autistic as that may make a difference.
You can also check your eligibility for benefits by checking with a benefits calculator such as this one.
I know many of you may be thinking I can't possibly be entitled to any benefits as I'm a teacher, however that is not necessarily true.
In my case I had an extended period of absence from work, which meant that I was on half pay. After some investigation I discovered that I was entitled to something called 'New Style Employment and Support Allowance'. This benefit is available to you, if you go onto half pay, providing that you have paid enough national insurance contributions in the previous two years.
Obviously everyone's situation is different but please don't assume that you won't be entitled to some kind of benefit. Even my ,excellent and well informed, union rep wasn't aware of my entitlement to 'New Style ESA'.