Under the complex tax rules, if the worker moves between different assignments but remains employed by the same company, they can claimtaxrelief on the expenses covering their travel from home to those different places of work.
The global equity derivatives division had already lost heavily last July (as, to be fair, had other investment banks), when the British government unexpectedly changed tax rules so that investment banks could no longer claimtaxrelief on dividends if shares are held for trading rather than investment.