AbstractUK constitutional law establishes priority rules governing the relations among legal sources. According to the implied repeal rule, a later statute is preferred to and repeals an earlier statute where the two cannot stand together. There is a vast literature testing the rule’s application in future-facing scenarios: whether Parliament in enacting legislation is capable of legally binding its successors. This article instead adopts a backward-facing perspective, focusing on past enactments. I examine Parliament’s legislative power to disrupt how implied repeal applies to earlier, inconsistent statutes. This sheds light on Parliament’s capacity to shape the constitution’s architecture—here, by rearranging priority relations among existing statutes. I juxtapose the technique against the doctrine of constitutional statutes, and also address the implications for the doctrine of parliamentary sovereignty. Nor is the technique simply of academic interest. A backward-facing reprioritising regime has already been established in the legislation governing UK withdrawal from the EU. Lastly, the argument may be generalised to encompass other legislatures that also enjoy powers to disrupt the implied repeal rule normally operating among past statutes.