All the answers are or contain place names or islands within the British Isles
The place names are in alphabetical order
21. Tweed jacket white shirt and blue tie (5) begins with H
33. Start of the working week by the sound of it (5) Starts with either an L or M
35. Neither top nor bottom for Minnie (6 5) Begins with M
36. Computer security in July (8 6) Begins with M
38. Not brave without courage (8) Begins with one of M N P
39. The weight exchanges 100 for 550 (8) Begins with one of M N P
44. Means of transport for birds (9) Begins with Q R or S
45. Doctor Evans Connor or Bramwell (5 8) Q R or S
47. This could describe you (5) Begins with S
49. Butch and Sundance (3 8 3) begins with S or T