How Long After Separation are the Eggs Fertilized by the Correct Roo?

[Lilorp14]

So I FINALLY got my mean rooster out of the breeding pen and replaced him with a nice one. He just started being evil this spring and I haven't been able to sell any chicks/eggs because I don't like selling people mean birds. Now that I have my nice rooster in, how long will it be before I can hatch some chicks that would be 100% fathered by nice boy? TIA!

 

[Deo]

Hens can retain sperm for up to 2 weeks and lay fertile eggs. Sometimes even up to 3 and a half weeks, so I’d wait about a month just to be sure the old rooster’s sperm has cleared out of their system before incubating any of their eggs.