The union’s advice is based on Leading Counsel’s opinion that you should ‘not going the extra mile’ as part of this action. Therefore while you should perform your normal duties if you cannot get them done either within your contractual hours or the weekly hours specified by the working time directive or finishing the task is putting you under considerable stress you should inform management that you have too much work for a normal working week and ask them for a formal, written response setting out how they intend to address the overload.
Where possible, quote from your university’s occupational stress policy which management need to honour.