Sunderland officials are ‘very frustrated’ at one thing in their ongoing search for a new head coach. Sunderland have been managerless since the sacking of Michael Beale on February 19th, more than four months ago. Fans are growing increasingly frustrated at the lack of movement on the manager front with the players returning for pre-season training in less than two weeks. Sunderland owner Kyril Louis-Dreyfus released a statement earlier in June, claiming that a head coach appointment was ‘imminent’. Soon after, the Black Cats saw Liam Rosenior pull out of contention to become the next Sunderl…