Hello!
A bit of context first. We added the early-access functionality to start providing CryptPad.fr paid users with apps they can test and provide us feedback before we open them to everyone. That because our paid users numbers are much much lowers than the free ones.
As @pirboazo described you can tweak the customize.dist/application_config.js
file but please be careful. Those changes may result in breakages with new releases, always read release notes thoroughly.
Follow the instance customization guide from our documentation to know more about how to change your instance look and behavior.