Welcome,
Similar story here in Yorkshire. It took me around a year or so from GP referral before my 1st appointment. The evaluation took place over a couple of months, finally getting my diagnosis about 6 weeks ago. However, the team that evaluated me did let my doctor know that I'd been accepted around a month after referral - so I would check with your GP in a few weeks, just to make sure that your referral has been processed successfully.
That seems to be a pretty typical time-scale from what I've heard from other people on UK autism forums.
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