I want to redirect mobile users to m.mywebsite.com as my website does not have responsive design. Should I use 301 (permanent movement) or 302 (temporary movement)?
According to Google, 302 is recommended if you want to redirect mobile users to a different URL. 301 should be used when moving from HTTP to HTTPS or you have a new domain name.
From this page https://developers.google.com/search/mobile-sites/mobile-seo/separate-urls - "For this purpose, it does not matter if the server redirects with an HTTP 301 or a 302 status code, but use of 302 is recommended whenever possible."