Entries must be in by 2pm Pacific Time.
Don't wait until the last minute to submit. You may lose your internet connection. Paizo's servers may go down because of a long-delayed Y2K bug, or a mad rush of people trying to post their item at 1:59pm. We may have a power outage. You may have a power outage. The whole country may have a power outage. We can't make exceptions for that.
Last year, some people found that if they had the submission window open before 2pm, and typed in their item, and hit Submit after the 2pm deadline, it would still submit. Even if that works this year, the deadline is absolute, and items that make it in because of this exploit will be disqualified because it's past the deadline.
Don't ruin your chance to compete this year by waiting until the last minute. Give yourself an hour, just in case.
And good luck!