Breeding my IRNs -housing

[BugsBirds]

Hello everyone, I have a few questions.

1. I've never bred IRNs before but I'd love to. I have a pair of IRNs. My cock is a Green Indian Ringneck. I believe he's a pure bred Green IRN because he has turquoise tints in his green feathers and yellow under his wings and tail. Also, I'm pretty sure my hen is a Pallid Indian Ringneck. She is 2 shades of yellow. A yellow-green and a bright yellow. She also has turquoise tints in her feathers when the light hits them just right. What kind of color mutations do you think they could have based on that information?

2. My Ringnecks are about a year and a half old. They're a month apart, my cock being the eldest. Cock was born in March '11 and my hen was born in April '11. I've heard that females should never be bred before they're 2 years of age and that males won't breed till they're 3 years of age. Is this true?

3. One more question. They have been living together since they were 7 and 8 months old. They get along well. Should I separate them during breeding season to prevent any premature breeding harm to my hen, or will the male not even try? I would like to keep them together but I don't want them breeding before they are physically ready. If they would be okay to breed this year then I'll gladly let them. Winter will be starting in a couple weeks and I'm live in southern California, US.

Any advice on these questions, especially the 3rd one will help me out a bunch. Thanks!
-Kimi