The longest I had a leopard gecko egg incubating that hatched successfully was 65 days and it was in Oct. so the ambient temp was a bit cooler. The longest I've had a fat tail egg go was 70 days or so. The most days I've had between clutchmates hatching (and both were healthy) was 5 days.
My longest before this year was 48 days for leos. Looks like I have some more days ahead of me then. Eggs look great, both are big and white. Can you tell I'm getting inpatient with these two eggs, LOL!!!