That's pretty early, especially if the L/F eggs aren't due for another 5-6 days. The problem is, if you take the chick out now, you may not be able to reintroduce it.
Personally, I would give them another couple of days to hatch naturally, then put any un-hatched eggs in an incubator (borrow one if you have to). Then when the chicks hatch in the incy, let them dry off before putting them under the broody at night.
Others may have better ideas though!