It looks like
JDiver might be working on this already (based on the "test thread" that was created), but when I click on the thread in this forum entitled "Adding a New Thread or New Post", it brings up an error message:
This page isn’t working
Flyertalk.com redirected you too many times.
I'm guessing the title of the thread ending with the words "New Post" is causing problems with the URL that is automatically generated. If possible, I think the solution would be to remove the words "New Post" from the title of that thread.