Oh wow. Okay so yeah the pullets, hens, and cockerels/roosters should all be on all flock, with oyster shells on the side. The pullets will only take what they need of the oyster shell as they come into lay, the hens would consume more of it, and the roosters would likely ignore it. It's not...
Are the cockerels also separate from the pullets / layers?
Chicks / pullets, laying hens, cockerels / roosters, and other poultry are each categories that if combined, could simply take the same all flock feed. I'm just trying to help make your life easier.
So if they are housed together they should all be on All Flock. The layers will take as much oyster shell as they need offered on the side, and the cockerels will leave it alone.
The body looks like my red bird I suspect is an SGE, but mine does not have white earlobes. Again, these things are a bit of the wildcard, so yes, I'd say that's also a distinct possibility. You'll see what color she lays soon!
https://www.backyardchickens.com/threads/chicken-with-white-earlobes-help-pics.310702/
This page seems to suggest that RSLs can have white earlobes if there is Leghorn in the mix.
Your girl doesn't really need to be on layer till you get the first egg, but if they are the same age and others...