Top bureaucrats at the giant Department of Human Services have gone missing from its negotiating team as the 35,000 public servants who work there prepare for another vote on a wage proposal. Union delegates have been left scratching their heads at the bewildering turnover in the senior management executives who have come and gone from the department’s bargaining team during the course of the lengthy wage dispute. A ballot will start on Friday with the department’s public servants to have their say on a new wage offer after the last “better than nothing” proposal was crushed in a landslide 83 per cent “no” vote in October.