Reply from PeltonLevel
Staff in middle ranking grades outside ATC (STAR 1&2, MSG 1&2, ATCE 1&2 - I don't know about ATC T&S) all give up the right to paid overtime when they take promotions to that level. In theory, they are entitled to plain time off in lieu of any excess hours, but the opportunities are not always available to take it. Unlike operators, their job doesn't go away when they walk away from their workstations!