The last time I went, which was a good few years ago now, I think it said you can't donate if you've been to South Africa (or had sex with someone who had) in the last XX months, if you're a homosexual/bisexual male or had had sex with a bisexual man, if you'd received a blood transfusion before 1970-something or if you had ever been paid for sex. Then there's stuff like if you've had a tattoo, piercing, glandular fever recently.

Oh no they do test all the blood. They do a finger prick test while you're there to test for anaemia and all the blood is tested for HIV and other nasties. I think it might just be to cut down on the risk of them wasting time collecting blood they can't use.

No bisexual males cannot donate. One of the pre-test criteria is 'have you had sex with a male who has had sex with another male' or something similar.

Gays/bisexual males can donate after abstaining from sex with men for a year now.

HIV is not detectable is what I meant for that period. Of course they test for everything, but they test for anti-bodies so HIV can be passed by transfused blood if no antibodies were present at the time of testing. Which is why the hefty screening criteria.