I just took one in Tesco toilet (classy 🙊) so it wasn't FMU by any means. I've only used these new blue ones once before when it was a genuine BFP with DS2. I used the test and thought I saw a line but then it seemed to disappear, so I took the test apart and could see a squinter. It's now dried and there is a line but it looks like it could be an evap 😬