first, i sense a basic fallacy. unless everyone is all in one meet together, who is in the 16 slots and with what time could change based on other meets. the last days before NCAA grabs the qualifiers are usually wild. so you may really need to look at where the 16 mark ended up in previous years, as the situation is dynamic. unless literally all 16 of you are in one place.
you're going about this all wrong. if 16 slots advance and you're outside 16, you have nothing to lose. the ones in the slots are the ones who have to defend their situation. you, it sounds like, have never run the PR time needed to make the 16, but are within a few seconds of it. so this is an opportunity to take a risk. there is no sense in either moping or having no confidence here. your chance here is to get your rest, get fresh, and then kick butt. kicking butt will not happen if you are all woe is me. save the postmortem for the offseason. you have a job. that job requires someone who believes in themselves for a week.
my question would be, it sounds like you run with at least some of these kids, and they catch you late. does that include these end-of-leaderboarders? do you take off fast and then they catch you? if that's the typical dynamic, my suggestion would be, find any of them in this race, and sit on their shoulder. that restrains you from emptying the tank too fast. that also puts you on the shoulder of the kids who can run the time you want. and i wouldn't even necessarily make it the 16th place kid. that's cutting it close. maybe more like 14th. that also probably addresses the "even out the splits" concern some voiced. go out a little slower, save a little. hunter instead of hunted. lock onto the people you need to beat. hunt them down. perfect world you make the 16, failing that, for future years you know you can beat them, and you know how to race different and better.