AIO SEO: Sitemap Indexes Setting
If in doubt, leave this set to Enabled.
Next, let's decide how many URLs each sitemap should contain.
You can enable Sitemap Indexes to show you a setting called Links per Sitemap.
AIO SEO: Sitemap Links
Each sitemap page should contain no more than 1,000 URLs. If there are more pages than 1,000 URLs, you will have to divide the sitemap into pages with 1,000 URLs each.
This will ensure creating each sitemap doesn’t take much more time than necessary, and search engines don’t give up if they take quite long.
What Content Should You Include in the Sitemap?
Next, we'll decide what content to include in the sitemap. There are two options here: Post Types and Taxonomies.
If you wish to include all posts, then leave the Include All Post types and Include All Taxonomies boxes checked.
If these two boxes are unchecked, you'll be able to see a list of all of your content types and taxonomies. From there you can choose which one you want to include on your sitemap.
XML Sitemap settings allow you to choose between Taxonomies and Post Types.
Note: Search Appearance does not display content that has been set to NoIndex or is removed from search engines.
These settings are for author archives and date archives that WordPress creates after you have published content. Because they are of little use in search results, you may not include them in your sitemap. However, you can enable these settings if you want them to be included in your sitemap.
Conclusion
Search engines are able to index your content and display it in search results, even if it is not in your sitemap. However, you can include content in your sitemap to make it easier for search engines to add, update, and delete your content much faster than waiting for them.
More Resources:
Get Indexed Fast
Google Sandbox
Links Help Google Discover You Faster
Thank you so much for your answer.
Nat
All the best!
Thanks for clearing up some points for me.
Lily