Hi Adam
welcome to the forum. The unit diary is available from the National Archives but unfortunately hasn't been digitised yet. It would be worthwhile contacting the NA to ask whether they are in process, or you could order a copy:
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2) 33 Heavy Anti-Aircraft Battery (omit the 'rd' after the 33).
You'll find two entries. The second one is the unit diary and you will need to take a note of the reference when contacting the NA - use 'order copy' to find out more