Is Yermak's exclusion from the NSDC and Stavka legitimate?

I saw the news that President Zelensky signed decrees and removed Andriy Yermak from the National Security and Defense Council, as well as from the Headquarters of the Supreme Commander-in-Chief. I wonder if the president has the right to independently change the personnel composition of the NSDC and Headquarters by his decree? Does the law provide for any additional conditions or restrictions for such decisions?