So I don't need to get any additional qualification?
You don't need any additional qualifications, but if the poo was to hit the fan on a report that you did and you have to prove your competency, then the 2391 goes a rather long way to prove that!
The NICEIC will happily take a QS on with only the the 2382 (17th ed), but you'll then still have to prove you're competent....