Is that an official extension of the deadline until Monday?
The deadline has always been Monday (December 17, 6am EST, to be specific), and that's not changing. Your game should still be uploaded by then. However, nobody's going to stop you from updating your game with a few fixes or improvements between then and the time I post the list, the latter of which won't likely happen before Tuesday.
Let's say this: Post your game by Monday, but if you upload a fix or two in the days to follow (especially if players are finding anything game-breaking), I'll still count it as a valid entry. In fact, we'll say Friday next week should be the cutoff for all game-breaking bug-fixes, especially those that players find and complain about, and at that point I'll be opening the window for votes.
Hope that's helpful.
Note: I will still likely post the list on Tuesday, and if your game's not on the list, then your game's not entered. But, Friday will give you three additional days to fix any bug that players find before voting opens. Once voting begins, players will be encouraged to vote on whichever version is the most recent. So, do with that what you want.
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