Running HTTP and HTTPS versions of the site side-by-side.
HTTP is canonical right now. Goal is to change that to HTTPS.
Created a new site in Search Console and submitted a new sitemap 4 days ago.
HTTPS sitemap is identical to HTTP sitemap (other than protocol). HTTPS sitemap has
lastmods showing the date the pages were updated.
Search Console shows all 1M+ URLs in the new sitemap as "Submitted" but it shows "-" for Indexed.
Wait until Google has indexed the new sitemap before 301 redirecting and changing canonicals?
Or 301 redirect and change canonicals now? Maybe Google hasn't indexed the new sitemap because they know it is not canonical?
lastmod: Leave as-is, remove, or set to current date?
Chrome shows HTTP warnings soon, so we're eager to move, but don't want to lose Google juice.