I started testing too early on CD5 straight after my AF finished and I got one blank circle then a lot of flashing smileys and then got my static.
CD5- Blank circle
CD6 - CD12 - Flashing smileys (6 of them)
CD13 - Static smiley
You are supposed to stop testing at that point as the static smiley stays on screen for 48 hours.
This might have been silly of me but I will just add the below.
I didn’t have much ewcm or pains or anything on CD13 so I actually then used a different CB device and tested again on CD14 when I got more symptoms and I got a static smiley straight away. This was exactly 24 hours after the first one I got.
And today I’m CD15 and I used the original device as it had reset and gone back blank and again I got another static smiley straight away early this morning. Then about half an hour ago I got a blank circle again.
So I think from that I perhaps had a longer LH surge more towards the 36 hours and I seem to have ovulated between 8am and 1pm today. As between that time I went from static smiley to blank circle.
Now I think you still have between 12 and 24 hours from the point of ovulation so I’m hoping mine lasts 24 hours so I can squeeze in another dtd tonight when OH comes home lol
Good luck to you 