This evening I went to the Victoria Clinic for my six-monthly sexual health screen, for the first time in, er, three years. (I plead nearly two years having been with no-one except my darlings.) I don't have HIV and will find out on Tuesday what else I have.
( Details of the TMI, posted in the public interest. Go on, you know you're going to click. )
If you're asymptomatic, it takes about a month for an appointment. But they're all very nice and good to deal with. I recommend them highly.