Based on pictures from June Crown it looks like the bones are cutting down on the zig-zag of the front opening.
As a “bonus”, the night before the event I decided I didn’t like the way the collar of the hemd was looking. So I removed the fabric from the inside of the collar (Because really, there’s no better time to drastically alter your hemd collar than the night before an event). This made the collar easier to iron to get a nice crisp honeycomb showing up.. but also allowed the collar to stretch out to MUCH longer than is actually needed for the neck. I’m not pleased with that. The plan right now is to make a new hemd with a smaller collar and then possibly come back to this shirt and fiddle with it later. I don’t want to tear apart my only hemd in order to fix it.. and leave myself with no usable hemd. So I’ll work on a new one first.