Unable To Edit Default Branch

Summary

I have branch X as the default branch, and I want to set it to Y. I can find no setting for it (after extensive googling, issue searching, etc.).

Gitlab-ce has a possibly related issue: https://gitlab.com/gitlab-org/gitlab-ce/issues/36048

Steps to reproduce

In a project, try to change the default branch. Fail to find a setting for it. (Seems like it should be in the project's Settings > Repository, but I've looked elsewhere, e.g., Repository > Branches.

Example Project

oohology-clients/bitemeals (private repo, but unless I'm missing something obvious (which is totally possible) this should be in any repository). I am an owner of the repository in question.

I'm using gitlab.com, which I believe is using Gitlab-ee.

What is the current bug behavior?

I search around and google and can't find a place to change the setting.

What is the expected correct behavior?

I would find a place to edit the setting, most probably in the project's Settings > Repository.

Relevant logs and/or screenshots

N/A

Output of checks

This bug happens on GitLab.com

Results of GitLab environment info

N/A

Results of GitLab application Check

N/A

Possible fixes

Something like https://gitlab.com/gitlab-org/gitlab-ce/issues/36048 would be nice.