I found an older thread with a similar issue but the solution did not seem to work for me. Explanation of issue: User logs in and SHOULD be directed to: https://example.com/ but the RESULT is directed to: https://example.com:80 This results in an SSL error for the user. The user can correct the URL and use the site as expected, I may have missed something simple but have spent some time troubleshooting and cannot find the issue!
For more information... (would be good to be able to edit my OG post) Signup form works fine and directs through to the member page. The php from the previous issue (albeit form 2016) has indeed updated the server port php variable from 80 to 443 but has not fixed the issue. Next step is to reinstall and see if it is a server issue or a setting issue. Reticent to do it as I had spent some time setting things up but given it not currently being useable this is the next step. P.s. Shame this forum is not more active, forums are usually my first port of call with issues rather than submitting tickets for every issue.
More information which might be of some use: Litespeed server on Ubuntu. Install was working fine for a few days as well. Then obviously I broke something before I noticed it stopped working correctly. I did update some server side things as well as some setting in WP and AM and that is why I am troubleshooting and trying to work back. Hopefully I can resolve it and I will update here if I fix it.
I'm an idiot. For future idiots like me. Cloudflare SSL was set on Flexi and causing issues. Changing to Full fixed the problem.