Just pick a point about 3/4 of the way there as your alternate, and don't worry. Hike at a speed you're happy with and decide when you get to the 3/4 point. As long as you don't measure your success or failure as to which point you come off it, but rather how much fun you're having in a day, you'll do absolutely fine.
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Any fool can be uncomfortable...
My 3 season gear list
Winter list.
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