New ovulation test 2bsure

Hi ladies,

Has anyone had experience with the new dipstick ovulation tests from 2bsure?
I've been using them for 3 years now, so I pretty much know how they work by heart. I ordered the same tests as usual last week, but I noticed they've changed type. The dipsticks look different, and especially... they don't react the way I'm used to!
Normally I always get a faint line, and when it starts getting darker I know it'll be positive the next day (just a bit darker), and then super positive the day after (much darker).
This time I already had a thick dark line right away (7 days before my expected ovulation). So just to be safe, I started testing twice a day because I thought my egg might come earlier, but nope
Now, 4 days later, still the same dark line, but not dark enough to be positive.
Is it true that these suddenly become positive and stay almost positive for the rest of the cycle? I have to say it's really annoying