Hi.
I wouldn't give layer until I saw the first egg. But, @junebuggena has it right.
I use "all flock or flock raiser" with 20% protein and oyster shell on the side. Not all of my birds lay. They are different ages and eventually some will molt while others don't. And I have cockerels. Too much calcium long term can cause kidney issues. Only the birds who need it will use the oyster shell. I think the higher protein is better when they are still growing or replacing feathers.
If you do switch to layer in the future, you don't have to throw out your grower.
I am no expert, just sharing what info I do have.
Congrats on your first flock! All nice breeds. And it's a lot of fun being able to tell them apart. Plus you might even be able to tell who laid which egg. When my BR are in the box I can't tell them apart. And their eggs are all about the same shape, color, and size.
Plus I have 48 chickens total with many just starting to lay. I can tell everyone else apart except my 3 BR. I love all the eye candy!
Hope you enjoy as much as I do!