Even harder goal for Sunday

Hitting 3:05:00 is tough enough, but I just checked one last time to see whether there were more people who have popped higher scores into the Top 85 and, lo and behold, there are. Now, instead of having to beat 3:05:00 to be pretty confident of being in the Top 85, I now need to PR, cracking below 3:02 to be pretty sure of being in the Top 85. Now to figure out what the best strategy is to make sure I hit that time. How much of a negative split should I attempt? Hmmm... (And, of course, this all assumes that the winner of my age group does NOT finish faster than the Platinum standard.)