Start promoting registrations. Like, put a banner on nice place, that has info about the pros of having registration. Then leave it for a month or two. And then implement needed registration.
Also, a simple header message about this change is needed 100%. Put it on top of the newly released chapters, and on the mainpage above all chapters. Just write into it about this change and that a registration will be needed + adding a link for registration. For all who are registered - they won't be seeing this. So only non-registered users will be inconvenied by this and they will try to register.
- Snah25, Argent Witch, isoycrazy and 34 others like this