While buses leaving the race are good they can get very long lines/waits and then From POP you'll have to 1st catch a bus to MK then monorail or walk to contemporary. So transport alone will take a good chunk of time. I wouldn't chance an 11:00am brunch unless maybe I was staying at Contemporary, starting in an early corral & running in 2 hrs or less. Rushing to an ADR to me isn't worth it.