CloudFlare Proxy / APO first time connection is slow(er)

Hi All,

I have a website on the free plan with Cloudflare APO and WPRocket (Wordpress).
When a users connects for the first time it takes a while to load. After that all pages are really fast. Just the first time visit.

When I visit for the first time in incognito its slow, open new incognito and first time is still slow.
Rocket loader is disabled.
Minify is disabled
TTL cache = 1 year

I use the cloudflare APO with WPRocket setup. I have some waf rules for managed /wp-login challenge and blocks on the xmlrpc.php. Does anyone know what the issue could be