Steam trains to change course - this will upset him! (13)

I believe the answer is:

stationmaster

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'course this will upset him' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.

'steam trains to change' is the wordplay.
'change' indicates an anagram.
'steam'+'trains'+'to'='steamtrainsto'
'steamtrainsto' anagrammed gives 'STATIONMASTER'.

Can you help me to learn more?

(Other definitions for stationmaster that I've seen before include "Railway official" , "Railway employee" .)

I've seen this clue in The Irish News.

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