[MM3-users] use_https not being honored?

Using Mailman core 3.3.5, and Mailman API 3.1, I have use_https: yes set in my mailman.cfg so that I can use https for calls to the API, however even in mailman.log, it still says it is using http:

[2022-06-01 09:35:54 -0500] [959009] [INFO] Starting gunicorn 20.1.0 [2022-06-01 09:35:54 -0500] [959009] [INFO] Listening at: http://hostname:8001 (959009)

GET and POST requests work fine if I use http, but fail when trying to use https. I have a certificate being used by our Mailman installation, so is there some additional config not mentioned in the docs to enable use of the API over https? I've only recently started using Mailman so if there are additional logs or system information I need to help with this?