Here is a simple method I like to use to redirect backlinks that are https for free.
If you have switched domains or bought a domain for SEO purposes. You may have attempted to redirect the domain via your domain provider. The redirects will work for non-https links, but not secure ones.
Step 1: You can point your domain really to any name server, none of the traffic will ever get redirect to it with Cloudflare. It just has to be pointing at something to set up an account.
Step 2: Setup a CF account for the domain, and Re-update the name servers to Cloudflare’s.
Step 3: Select a flexible SSL in the SSL/TLS menu page.
Step 4: In the page rule menu page. You will want to set a generic catch-all and forward them to the home page of the new domain.
If you have any pages you want to redirect to a specific page, like contact us page, or RSS feed. You will have two extra rules you can setup for free.
Give it a day, and should see all your https links working and redirecting to the new domain.