وَبَعْضَ أَحْكَامِهَا
And some of their rulings.
The word some matters. The statement does not entail that every earlier rule is negated in exactly the same way. A ruling may be changed, its underlying principle may remain, or a later revelation may clarify its application.
For example, affirmation of divine oneness, honesty and justice remains tied to the truth of revelation, while particular practical regulations may differ across communities. The applicable ruling is established through the final authoritative religious evidence.