I found two occurrences of a License version:
README.md - GPLv2
setup.py - GPLv2+

Where did you find GPLv3+ ?

README.md information is original since 2015
while setup.py file was created by me in 2021. I probably copied (and modified accordingly) the file from a different project without any intention of changing the license of fedpkg-minimal. I didn't check that there is a different value in README.md. So I would say the overall license version should be the original one = GPLv2. But I am not an expert in this field and don't know the specific differences (I guess 2+ is less restrictive) and don't know the process of how the license version should be correctly changed.

GPLv2+ is also mentioned in the RPM spec file:
https://src.fedoraproject.org/rpms/fedpkg-minimal/c/2d4db101bdc19f98035f9958fdb837187d3ebc29
That commit is from 2015.

This commit added the copyright header into the script and used GPLv3+.
https://pagure.io/fedpkg-minimal/c/c3ec5bf1cf42e42f8919940f4b657c539ecf48f3
This is also from 2015, but a month later than the spec file.

@pbabinca, do you remember anything about licensing here?

This commit added the copyright header into the script and used GPLv3+.
https://pagure.io/fedpkg-minimal/c/c3ec5bf1cf42e42f8919940f4b657c539ecf48f3
This is also from 2015, but a month later than the spec file.

@pbabinca, do you remember anything about licensing here?

I have found following mail exchange with @ausil

(me)

I'm going to add copyright header into fedpkg-minimal. Just to be sure -
it that package
http://koji.fedoraproject.org/koji/buildinfo?buildID=485120 copyrighted
by Red Hat, Inc or did you use someone others code there?

(Dennis)

It was my code, so using Red Hat Inc is fine

The code predates my era and I think Dennis might provide some insight about the license.