What's the point of it not passing away if there's no need to keep it?
The law foreshadowed the gospel. We don't follow instructions to slay lambs, but the efficacy of the slain Lamb of God is being fulfilled. Till heaven and earth pass, one jot or one tittle shall in no wise pass from the law, till all be fulfilled. The law will continue to point to Jesus' sacrifice.
I figured Jesus would supersede anything Peter had to say.
No, you can't weasel out of this one. You said that Peter said to follow the law. You screwed up.