The contest is extended till Sunday (25th) 10:00am EDT, feel free to submit now to all 4 challenges.
We think now that the difference in scores had nothing to do with architectural differences between the CPU and GPU setups, nor were our test servers hacked, as some of you suggested. It seems that at the end of the CPU-based testing period the set of target test days had one extra day compared to the set that we planned to use, that's why you saw different scores in identical submissions. We are still investigating how this could have happened. We also think that the current setup is correct in all 4 systems. To compensate for the downtime and the submission issues we extended the contest with ~2 days. Apologies for the inconvenience caused by this.
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