The post tags needs to be divided up into multiple files when there are over 50,000 tags... We have 66,971 Tags which are used for microcategorization.
Errors
Too many URLs
Your Sitemap contains too many URLs. Please create multiple Sitemaps with up to 50000 URLs each and submit all Sitemaps.
Sitemap: domain/post_tag-sitemap.xml
Tag: urlset