Ostrich Eggs Resetting

[Squeak]

I have two ostrich incubators in my barn. One ostrich is the only occupant of the barn. When I put the eggs in the incubator, the days count down. When I get to the last day, the countdown to hatching resets. The first Ostrich took three weeks to hatch. She grew up and laid an egg, which I put in the incubator. The egg kept resettling the time. She laid another egg and I created another incubator and put the new egg in the new incubator. Now both reset. :-(

I got the incubator recipe by doing the quest, so I have no idea which mod would affect this.