Dear loyal Ken,
On this site, I have known you to be big hearted, and very thoughtful. Those are rare gifts. You can apply them in many different ways.
After 16yrs at the 9's, you may be finding that young men have so much more energy and strength than those in their thirties and forties(just guessing). I think you might find a slower pace good physically and for your family. Working nearer to where you live lets your kids walk by and boast to their friends,"That's my Dad."
For me, I would guess that you might fall apart probably not. But if you do, then you will be in a situation to do the work you need to do so as not to be an adrenaline junkie. I'm not saying that lowering your level of hypervigilance will happen. I think you will be exactly who you are where ever you are. You are strong.
I had a difficult time changing my work place too. The same issues loyalty, responsibility, comradery. I hope my christian faith will not be a problem for you. So you can take this next bit any way you like.
There is a line in one of the psalms that says, "they will raise up like eagles..." I read an article from the Smithsonian magazine about how eagles migrate from Turkey to the Sinai. They ride the thermals. When the psalm was written, it would be common to see towers of slowly circling eagles. As an eagle rises on a thermal current, the air starts to cool, not giving him much lift. The eagles are very far seeing so he could just look over to the next column of eagles and soar down to the bottom of that column and rise up again....migrating more than a thousand miles without even needing to beat his wings much.
Maybe you are at the top of your current and can float down, easier than you think, to the next column of firefighters the way the eagles do. There is a time for everthing under heaven. Is this your time? Only you will know and the change may be scary. H#*l, you've been scared before right?