With month-long competitions you tend to see some submissions up-front and the rest at the end, nothing in-between. Can I recommend either two weeks, or have a month-long one but with weekly "milestones" where a winner (or two) is picked out of each week's submissions and the final four/eight are faced off at the end of the month in one final vote. This makes it so that for larger submission counts the whole thing doesn't get bogged down. The weekly milestone winners only get bragging rights, but have good reason to keep submitting because the more entries they get in the final four/eight, the better their chances of getting a real prize.
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