Currently, PEP-1 recommends that new PEPs be submitted as "PEP 9999", and then a PEP number will be assigned by the PEP editors upon approval.

What happens in practice is that a PEP editor looks up the next available number when the PR is created and tells the author to use that. This feels like an unnecessary complication. I suggest that PEP authors should instead just pick the next available number when they create their PEP. If there is a conflict (e.g., two PEPs submitted around the same time with the same number), the PEP editors can pick which one gets which number.