In the Python spirit of "it is easier to ask forgiveness than it is to ask permission", I took the liberty of removing all pending releases, because they seemed unneeded: https://dist.plone.org/release/
For example, there was a 4.3.13-pending which will never get turned into an actual 4.3.13: for some reason we skipped ahead to 4.3.14. Anyone who was brave enough to use 4.3.13-pending in production, very likely switched to 4.3.14 years ago.
Also, some symbolic pending links were broken.
What I do wonder, is if 5.1-pending and 5.2-pending should have remained. Is anyone using those? It could be useful to have a package or project tested against 5.2-pending, if that means that currently it points to 5.2.1, and once we have a real 5.2.2-pending, it would point to that. But that is almost the same as 5.2-latest, and would only differ for a few days a year.
Anyway, here is the list of pending releases that I have removed. Actually I have moved them to my home folder, so I can put them back. If anyone actually needs them, just ask.
Mar 28 2017 4.3.13-pending
Sep 10 2017 4.3.16-pending
Jul 20 2018 4.3-pending -> 4.3.18-pending [broken]
Dec 18 2015 5.0.1-pending
Aug 5 2017 5.0.9-pending
Jan 9 2019 5.0-pending -> 5.0.10-pending/ [broken]
Sep 4 2019 5.1.6-pending
Apr 19 2017 5.1b3-pending -> 5.1b3
Jan 8 2019 5.1-pending -> 5.1.6-pending/
Jul 19 2019 5.2.1-pending
Jan 14 02:30 5.2.2-pending
Jan 14 02:30 5.2-pending -> 5.2.2-pending/
My plan was to start creating the pending folder for the upcoming release early and push package releases into that early and often. The 5.1-pending and 5.2-pending would point at those upcoming releases, so that anyone using them for pre-release testing wouldn't have to update their jobs with each release. I've been bad about keeping on top of those package releases though, so it hasn't been particularly useful yet.
Funny: the other day I was looking at an older package and it was pointing to the 5.1 pending release, so I updated it. If someone was relying on a pending release in a buildout, they know what they’re doing and can easily obtain the version pins if they need them. Cleanup is good!
I agree with @tkimnguyen
If there is nothing pending, the link should be removed. IMO it is more confusing than it helps. Its good if it breaks - in this case at least.