Each team has between one and three Specialists and it's a management band so form part of the overall team leadership. They don't directly line manage Planners (the Specialist's manager line manages the Specialists and Planners), but do take an active role in looking after Planners and leading the day to day work. Some Specialists will lead the on the job training and coaching of Planners whilst others are more technical and deal with systems as hinted above. They deal with the bids that come in and allocate them to a Planner, daily performance and delays, issues that crop up that require an intervention, produce some documents, provide updates to their manager, talk to ops and operators, cover for the manager when they are on leave or out the office, lead weekly conference calls and technical "round the machine" meetings. They can be hands on planning but generally assist and guide others or are dealing with a specific issue that's been escalated.
A good Specialist is worth their weight in gold and are well thought of and respected, it's a tough job juggling many issues and tasks. There are a few managers too who maintain a logon to the database and jump in every now and again either to help out and keep their hand in or to make / sign off a final decision having had a look at it on the graph.