Assuming you are talking about the
Quick Links > Today's posts function to my knowledge query results are based on a snapshot of threads added/updated in the past "24 hours."
So results you get "now" will most likely be different than the results you would get an hour or two from now. Oldest threads will drop off the end; newer threads will show up at the top.
Does this help or did I miss the boat (again)? (Wouldn't be the first time.

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