Help needed troubleshooting hatch problem

Okay, I'm hatching backyard mix eggs. First hatch went well, 90%+. One pipped down instead of up and I guess drowned, 1 quit late for no apparent reason, proper positioned, no pip.

Second hatch not so good. 80% hatch, a few of them pipped the wrong end. One more drowner, 7 that never pipped. Most of those were backwards, all 7 fully formed. I wondered if a temp drop about day 16 combined with me taking them out of the turner and laying them down was at fault.

Third hatch was better, out of 39 that started developing, 37 made it to lockdown. I waited until day 18 to take them out of the turner, no temp drops. 33 hatched, with all appropriately placed pips. Of the other 4, 1 pipped internally and quit (and had already started to smell a bit). 2 were properly positioned, 1 was under the left wing. Those 3 never pipped.

Any ideas? I'm using a Hovabator Genesis, running around 30% (dry) days 1-18, then 60%+. Close to 100F. I'm also using an incutherm to make sure of temp/humidity.

Seems that I'm having the same issue each time, compounded on the second hatch. What should I do?

Have a read of this article ~ https://www.backyardchickens.com/a/egg-failure-to-hatch-diagnosing-incubation-problems

Sorry to hear your hatches have not been so good. A temp drop at day 16 should not have affected the eggs. If they were under a hen she would get up each day and leave the nest to poop, eat and drink so that would be just the same. My incubator has a cool down option that turns the heat off for an hour everyday to replicate the hen leaving the nest. I would not worry about you opening on day 16.

Hmm, that might have given me more questions than answers. How much fluid should be left in an unpipped egg? I figured the extra was due to dying before finishing, but...shouldn't holding around 30-32% humidity be good until lockdown?

Almost laughed when I saw inbreeding, not a problem I have, my rooster isn't even the same breed.