 The club spent over a decade in Division 1 until 1990/91 when they gained promotion to the Premier Division.Llandyrnog were crowned champions at their first attempt and promoted to the Sealink Welsh Alliance.After a lengthy spell in this league Llandyrnog were relegated back to the Clwyd League Premier Division where they stayed until 2002/03 until manager John James was appointed and the club gained promotion back to the Welsh Alliance.