Fulfill means fill full — arrive at the intended end — not erase and postpone.
The Law was a tutor and a covenant administration. The Prophets aimed at a coming day. Both terminate in the Messiah.
Matthew 5:17–18 sits next to “heaven and earth passing.” Matthew 17 puts Moses and Elijah on the mountain and then leaves Jesus alone.
When the temple fell, the public system that had administered Moses as a standing world-order was removed. The fulfillment was already the Son.
You are not under a tutor waiting for a later graduation. The goal has a name.