I'm trying to override the message used in, retrieve_password_message() filter. The problem (i'm beginning to think) after almost a week of trying is that I'm using custom auth forms, custom-login, custom-register and custom password-lost and reset pages. These are redirecting all logic away from the built in forms. They all work as expected apart from when i try to customise the reset password message. No matter what i try it seems to just load the default message in wp-admin core. If this is the problem then I'll just leave it but i need to know its got beyond ridiculous! The filter method is situated inside the same class as all other custom form logic.

public function replace_retrieve_password_message( $message, $key, $user_login, $user_data ) {
        // Create new message
        $message  = __( 'Hello!', 'cust-auths' ) . "\r\n\r\n";
        $message .= sprintf( __( 'You asked us to reset your password for your account using the email address %s.', 'cust-auths' ), $user_login ) . "\r\n\r\n";
        $message .= __( "If this was a mistake, or you didn't ask for a password reset, just ignore this email and no changes will be made.", 'cust-auths' ) . "\r\n\r\n";
        $message .= __( 'To reset your password, visit the following address:', 'cust-auths' ) . "\r\n\r\n";
        $message .= site_url( "wp-login.php?action=rp&key=$key&login=" . rawurlencode( $user_login ), 'login' ) . "\r\n\r\n";
        $message .= __( 'Thanks!', 'cust-auths' ) . "\r\n";

        return $message;
}