When do EE normally start to lay!?

[JJSS89]

You could, as long as you don't have any dumb young hens who want to eat the egg.

Since the RIR is laying earlier than the EE, I would say the EE will get the idea anyway.

 

[song of joy]

Point of lay varies quite a bit with EE as they are mixed-breed hens. I have two EE. One began laying at 24 weeks and the other at 30 weeks.