There is a trick that can be done with success if done correctly.
Using food color on the vent of a chicken , traces of the color will end up on the egg. There are limitations, of course since there are only 4 major food colors available easily. (there may be more, but I just looked at what was here). With 11 hens, well, that puts you at a shortage.
Your best way to place eggs under a broody would be all at same time. That way they hatch at same time. You would collect the eggs until you get desired amount, and then place them. Another good idea, at that time, is to mark those eggs with an X. This way if other hens add eggs after broody starts to incubate, you would remove all without X. You want to avoid a staggered hatch for best results.
WISHING YOU BEST,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
