wp-register.php still available

Hello,

I think this plugin is awesome.
Anyway I have this issue, I do not know if it is just me.
Basically after more or less 24 hours from plugin installation, attacks to my site started again. So I looked for possible ways to guess the new name for the login page. I found that the address http://www.mysite.com/wp-register.php is still reachable and the new login folder name can be easily extracted from that.
As this file (wp-register.php) does not actually exist in my installation directory, I assume that the redirect information is hard-coded somewhere in the DB.

Any other?

https://wordpress.org/plugins/rename-wp-login/