Mellowmalt
Songster
bit of a mute point as he has movement in his 4 eggs so I'd say that already indicates fertility.Have you cracked one of the eggs to check for fertility?
I'm just baffled how temps are being controlled without a thermostat. I'd hate being the reason for a deformed hatch which is why I double and triple check temps, not so much to make them develop but to avoid them developing badly.