Gen,

First thing that will happen is that the current July/August Challenge will close: all the map threads in this directory will be locked, and a new "poll" post will be created so that people can vote on their favorite map.

Then the poll will close, and a winner will be declared.

Then, when the mods get to it, all the threads in this forum (except for this one) will be moved to the "archive" forum, and a new post will be made announcing what the new challenge is.

There's no deadline for entering, until the threads are locked at the very end of the contest when voting begins.

As to exactly when the new challenge will be posted? If there's a better way than "checking every day", I haven't learned what it is yet .