Bucknall was promoted to brevet lieutenant colonel on 1 January 1936, and attended the Royal Naval College, Greenwich. From 13 March 1937 until 12 April 1939 he served as an instructor at the Royal Military College of Canada, taking over from Gordon MacMillan, where he came into contact with some of the Canadian generals of the next war, such as Harry Crerar, the college Commandant, and E. L. M. Burns and Guy Simonds, both fellow instructors.
Bucknall was promoted to brevet lieutenant colonel on 1 January 1936, and attended the Royal Naval College, Greenwich. From 13 March 1937 until 12 April 1939 he served as an instructor at the Royal Military College of Canada, taking over from Gordon MacMillan, where he came into contact with some of the Canadian generals of the next war, such as Harry Crerar, the college Commandant, and E. L. M. Burns and Guy Simonds, both fellow instructors.