Flint stable 4.x firmware

I thought I had seen firmware 4.x as stable for Flint on glinet download center. Now I cannot find it anymore, does anybody know why?

download from here for the time being

Sorry, we deleted it by mistake.
It has now been restored.

I thought it was pretty stable. Flint is running:
AdguardHome (OSID Full list)
Wireguard client
Crashed due to low memory after a uptime of 23 days running 20-30 devices. Restarted and was up in 2 minutes.