If the seed broke soil lose the humidity dome.
that would depend on the humidity of the area. I poped seeds in January and when I took off the dome a couple early leaves dried out on the edges and slowed them down a bit the humidity was 11%
If the rh is 30 or over your probably safe to remove the dome. if the rh is low when you go to plant and a dome dosnt fit you can use soda bottles with the bottom cut off