It turned out my belief on this point was correct, so there’s now a shared PEP 607 that covers common background points, and provides a neutral overview of the key differences between PEP 602 and PEP 605: PEP 607: Shared background for the release cadence PEPs
I’m also making some minor updates to the text of PEP 605, but nothing that fundamentally changes the proposal (just rewording a few sections based on the creation of PEP 607, updating it to account for NEP 29 updates, and making it more explicit that the Steering Council and release managers aren’t locked in to abide by every single aspect of the concrete proposal, even if they accept the PEP as a general way forward): PEP 605: Update for PEP 607 publication by ncoghlan · Pull Request #1212 · python/peps · GitHub