From previous years' contests:
8th-prize 13th-leaderboard
8th-prize 14th-leaderboard
10 16
10 14
10 15
10 23
10 23
This year, there are more prizes (20) than ever before. So, extrapolating from previous years' prize eligibility ratios, it looks like if you can finish in the top 30 on the leaderboard, you'll most likely get a prize.
Therefore, if your goal is to win something (not necessarily get 1st place), you can bank when you're #25-30 (not tied). The big question is whether the leaderboard will be trimmed down to that size by the end of this contest, which doesn't look very likely at this point, but you never know.
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