I never tested it out, but I will warn you that I got a devastating false pos at 10 dpo. At 11 dpo, retested and got the neg. 2 years later after our ivf, I waited until 12 days to test, just to make sure it was gone. Got a real bfp on that one!!!
Sorry if I haven't gotten back with anyone via PM. Still learning the iPhone app and not very "techy".