Hi Tirsor.

General challenge rules state that:

Original work - The map must be made within the time frame of the challenge. Therefore it is not allowed to use a previously made map or continue work on a map begun before the challenge commenced. This to make sure that all have the same chances in the competition.
You can read the whole README post here: https://www.cartographersguild.com/showthread.php?t=503

Since you did this map last year, it doesn't fit the time frame. The challenge is to dig out and redo the entire map within the Feb 05-28 time frame, which gives artists about 23 days. Maybe you have another map you'd like to redo? I know time isn't too long, but that's why it is a challenge, after all.