In London Underground Ltd v Ferenc-Batchelor and Harding v London Underground Ltd, the EAT holds an "informal oral warning" - which was in fact confirmed in writing, continued to have effect for up to 12 months, formed part of the employee's disciplinary record and could be taken into account by management if a formal disciplinary process was instigated - in reality constituted a "formal warning", giving rise to the statutory right of the employee to be accompanied to the disciplinary hearings that resulted in that warning being given.