I have a BIG site. Reciently when I changed the site from http to https I regenerated all 20 sitemaps. I put the old ones in a folder "old_sitemaps" and submitted the new ones in Google Webmasters Tools. Today I am looking at Google Search Console and I see the only sitemaps that it has are the ones that I had put into the "old_sitemaps" folder. The correct sitemaps are on Google Webmaster Tools. So now I am wondering what is the best solution for this. I can simply delete the old sitemaps from the server and then resubmit the correct ones in Google Search Console. That was my first reaction. But I am wondering if someone has a reason why this is not a good idea. Can I put a 301 redirect in the htaccess file? Is that a good idea? I don't want to submit the new ones until I'm sure that Google is not paying attention to the old ones. I don't want to get penalized to submitting the same urls two times
Hi! U should try to read info about Migrating from HTTP–>HTTPS on Search Console Help Center https://support.google.com/webmasters/answer/6033049
If you delete the old ones and submit the new one, you will be fine. It will take some time for Google to figure it all out but you will not be penalized.
I also had a very large site where the XML sitemaps were not being indexed. So on the home page or contact us page that get indexed all the time, add the URLs to the site maps. This will put them into the list. However, also use GSC to resubmit them. This means, delete the sitemap from the GSC>Sitemap then add them back. This will also get Google to read them.