When is a good day to test?

Patrice • I had my little rainbow 5•12•15 Olivia is such a happy baby & I`m so blessed!!
I'm about 4dpo, I know right now it's too early to test, but when is the best time to? Since I ovulated early this month, the app says I'm due March 10 for AF. If I were to test before then when is the best time to?