I am not due my period until Monday but even that's a guess as I'm irregular. I took two early tests/two different supermarkets, Waitrose and Asda yesterday as I've been having other symptoms for about two weeks now. Nothing happened in the time frame but a couple of hours later both had a line. I know you are not supposed to read them after time frame but is the likelihood quite high for evaporation lines once dried out with two different tests?