Indeed the officer in question was quite within his/her rights. That said, I'm not sure that the word "bollocks" carries that much of an offense nowadays. Ironically, I have a friend in the Border Force who is also a town councillor. On skittles evenings, if he had imbibed too much during the lunchtime session, he would occasionally venture out in a T-Shirt embazoned with the words "Even God knows you're a c**t".
I wonder whether he would dare wear it when flying abroad for his hols