Yes. As in the guidelines:

The point is to get you disciplined into writing every day, but life sometimes interferes with even the most disciplined person's good intentions. Therefore, you may catch up on assignments from previous days, so long as you don't go more than three calendar days without posting (based on your local time)


So, you will likely see some people posting a few day's worth at once if they're working ahead or playing catch up.

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