it’s normal to have a couple early hatchers.....in my experience with myshire eggs (before my incubator decided to screw up) most of my “healthy” hatches occurred in the first 24 hours of day 17 (which started for you this evening). you can have a couple early and a couple later and still be in normal range. If you happen to need to allow eggs to settle again, I would recommend storing in area below 70*. I keep mine in laundry room/bedroom area that generally stays 68 or lower.And then there were two. Both of my batches have hatched one by one over days. Is this normal?