Confused. Who laid this egg?

[Emvega12]

I let a broody hatch eggs I got from a someone on facebook. Just a backyard mix so I was okay with any outcome.
Only 1 chick hatched on sept 1st , out of a green egg.
Today i saw the pullet sitting on a nest and then i went to collect eggs and there was a blue one! I have no blue eggers
I have olive and brown eggers.

Is it possible for a 10 week hen to lay?

Is it possible for a blue egger to come from a green egg?

What do you think this pullet is crossed with?

 

[Jener8or]

She didn't lay that egg, I'm pretty certain. I think the blue egg is from an Olive Egger and just didn't get as much brown pigment at the end of the laying process as it normally does.

 

[Emvega12]

She didn't lay that egg, I'm pretty certain. I think the blue egg is from an Olive Egger and just didn't get as much brown pigment at the end of the laying process as it normally does.

Okay I didn’t know that could happen. Makes sense, would be a big first egg too lol. Thank you

 

[Hazel feather]

I agree , an olive egger laid this egg . She doesn’t look mature enough to lay yet and that would be very early to lay an egg.