When can I start vent sexing my button quail?

[Coturnix_Quail]

My quails looks male and its 8 and a half weeks old but it doesn't excrete the white substance so does that mean that its a female the quail im talking about is my profile picture

 

[ButtonBag]

Do you have a picture of it now? Has it crowed (a wind whooshing noise) or run around with its wings fanned out?

Edit: I've seen you've posted this on a lot of different threads. So is it a button quail or not?