Cloudflare Always Online evicts pages from cache early.
Cache-Control headers defined as no-cache and/or must-revalidate:
# curl -svo /dev/null http://example.com/
< Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Bug in Cloudflare Always Online cache handling where pages can be evicted from cache early if they include headers that would prevent caching.
Add the following line to Domains > example.com > Apache & Nginx Settings > Additional Nginx directives to remove Cache-Control headers: