The situation is different because in this case the resulting (permanent) change in the employees' commute was something they couldn't have been aware of at the

The situation is different because in this case the resulting (permanent) change in the employees' commute was something they couldn't have been aware of at the time they signed the employment contract. For care workers working on site at clients the varying commute is a condition of their employment at the time they sign the contract. Unless the client's home is in an extremely remote area, there's nothing wrong with the varying commutes.