At what age can vaccinated birds go with unvaccinated birds?

[KB91]

I currently have 16 week old Bielefelders, 13 week old EEs, 9 week old FBCMs, and week old legbars. None of them are vaccinated simply because I forgot all about it with the first batch I hatched, and didn't want to risk making them sick by vaccinating the rest. I am not against vaccines in any way and would have if I remembered. Now if I got vaccinated birds or chicks when would it be safe to mix them together?

 

[SunHwaKwon]

Vaccinated for what?