Members Plugin set default content protection roles by Custom Post Type

members-protect-cpt-default-roles.php

<?php
add_filter( 'members_default_post_roles', 's9_members_force_content_protection' );
function s9_members_force_content_protection( $roles ) {
	if ( 'minutes' === get_post_type( get_the_ID() ) ) {
		$roles = array( 'board_member', 'home_owner' );
	}
	return $roles;
}