I've had them pop out and one look at them, can tell they are male too.
Had to look back at my notes lol. That was a rough hatch for me, and unfortunately I didn't track which ones started in which incubator. I moved them all to the same hatcher, I think I moved the slower set a half-day later. I just remember I allowed an extra day to the overall hatch.
I had set 42 eggs total, removed 4 clear/early quitters, so 38 made lockdown, but only hatched 29. I had 2 die after zipping all the way around, but didn't fully rip the membrane and gave up before they pushed out, I was away at work. I saved several more that zipped and stopped, but I was home. Another one died on its back in the incubator, stuck between two eggs. Weirdest hatch for me ever!
I attribute some of those problems to some of the eggs being older when set. I don't think the temperature difference was any real issue, because I had used the Eco at its lower temp with plenty of success too. I think its just the difference between hatching on days 20 and 21, to hatching on days 21 and 22.