I did the first HPT using afernoon pee on 11DPO. It was a feint line, but definately a line. I have now done 4, the most recent one yeterday (I think 15DPO?) with morning pee and the test line is as dark as the control line on the most recent one.
I was very suprised to get a positive with afternoon pee as early as 11DPO. It was something I didnt expect!