Hello. HSTS isn't enabled.
The redirects have always worked before the latest version. That's the whole point to allowing multiple domains in Mojo and the preferred domain. I'd think. Otherwise why even have those options if mojo will only accept one domain? Something changed. I have 50+ pointer domains that have all stopped working. Multiple pointer domains is a fairly common need.
Here's a working example of an older CMS install (v 2.7.0.0):
This non-SSL (http://www.versascreengutterprotection.com) domain redirects to the preferred SSL domain: https://www.edgemeltsystems.com
Another example in a v2.7.0.2 install:
http://www.gsbservicesllc.com points to https://www.mysheetmetalguy.com
Any new CMS installs such as 2.9.0.1 do not work. I'm not sure v2.9.0.0. Worked or exactly what latest version it stopped working, but I think it's the latest one since the last time I set up a pointer domain it worked fine. I'm just noticing it in this latest version.
I hope this provides a hint.