Good luck on your commission!
Yeah, haha. I did not want people to feel rushed. |D
No, they will not become void.
It means that they are all taken into consideration.
However, one person would not be able to win more than one spot.
For example, if you entered three times, but the first two you wrote weren't as good as your third attempt, I would consider the third attempt more heavily. Basically I made this rule to limit the amount of entries, but give people more of a chance to win. Because sometimes an idea will pop into someone's head later, or maybe they feel they could do better after entering.
Hope that cleared things up.