The last Monday in May has been a bank holiday in England (which in England also means a public holiday) for many years now. One recent exception was in 2002, when it was moved to the first Monday in June so that it was adjacent to the following day on which the Queen's Golden Jubilee was celebrated.
Many years ago Whit Monday, which is seven weeks after Easter, was the Spring Bank Holiday, but about thirty years ago it was decided to fix it as the last Monday in May. The change saved confusion, as many people had no idea when it was to happen. Maybe the Early Spring Holiday will be changed sometime in the future, and not be fixed to the variable date of Easter.