I was also testing using strip tests some cycles too as I didn't know if I trusted the dual hormone digis lol. Was right for me, 98% of the time I oed day after solid smiley, the other 2% was when I got the solid once on o day and and a couple times 2 days after when I started testing at night too. That's why I went back to just fmu lol. I did many many cycles using these digis so luckily for me they've been super accurate! Hope they are the same for you!
https://www.fertilityfriend.com/home/519b48