Sorry there is some error here.
The Bn were not in HK in 1951 as they landed in Korea at Pusan in Nov 1950.
Please see this picture of them embarking from the UK:
http://royalirishrangers.co.uk/picts/korea1.jpg
It's dated 1 October 1950. The rest of the Brigade travelled with them at the same time leaving early/mid Oct and disembarking in Korea some 4 weeks later.
So whilst they may have stopped off in HK en-route to Korea they were not garrison troops and had previously been based in east Anglia.