Right from the F&W rules thread:
Only the author may bump their thread when posting a new chapter.
If you are not the author, you may not bump the thread in question. For the author, it might take longer than a month to write a chapter. They are allowed to bump threads to only post their new chapter. Any other reason to bump their thread or anyone else bumping the thread will result in the thread being closed.
So you can post a new chapter and you won't get in trouble.