Database Error on Relationships after update to latest MetaBox AIO and WP 5.5.1

Hello,
On all my relationships I get this error, with no change on my code that worked fine before. This is not limited to this relationship, it happens on all of them. Other then the error, the query results are returned correctly and shown on my pages so I’m assuming there is one query fired per relationship that messes things up. Can you help troubleshooting this?
I’m assuming the issue is at “AND mbr.to IN ()”.

WordPress database error: [You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ‘)) WHERE 1=1 AND wp_posts.post_type IN (‘post’, ‘page’, ‘attachment’, ‘itinera’ at line 1]
SELECT wp_posts.ID , mbr.to AS mbr_hotel_to_city_to FROM wp_posts INNER JOIN wp_mb_relationships AS mbr ON (mbr.from = wp_posts.ID AND mbr.type = ‘hotel_to_city’ AND mbr.to IN ()) WHERE 1=1 AND wp_posts.post_type IN (‘post’, ‘page’, ‘attachment’, ‘itinerary’, ‘top_activity’, ‘suggested_hotel’, ‘restaurant’, ‘city’, ‘shopping’, ‘room’, ‘hotel_activity’, ‘hotel_service’, ‘hotel’, ‘booking’) AND (wp_posts.post_status = ‘publish’ OR wp_posts.post_author = 2 AND wp_posts.post_status = ‘private’) GROUP BY mbr_hotel_to_city_to, wp_posts.ID ORDER BY mbr.order_to