The U.S. Postal Service is leaving the door open to involuntary layoffs as it seeks to downsize its managerial and administrative staff, part of an ongoing effort to reorganize the agency.

USPS first announced it would offer voluntary early retirement to eligible non-bargaining unit workers in early March. It declined to say how many employees it was targeting for the staffing reductions, announcing only it would finalize its plan in May.

Ahead of that rollout, postal management has not ruled out reductions in force, the government term of art for layoffs. The National Association of Postal Supervisors, the management association that represents most of the impacted workers, said USPS has informed the group there could be a RIF forthcoming. Much will depend on how many employees accept the early retirement offers, as well as how the Postal Service’s final structure and staffing plan takes shape next month. The early retirement offers, which did not come with any buyout incentive, were part of a “RIF-avoidance” process.

“There will be employee impacts as a result of district closings and administrative reductions,” said Dave Partenheimer, a USPS spokesman. “The specific employee impacts have not been determined at this time.”

Employees must be at least 50 years old with 20 years of federal service, or any age with 25 years of service, to qualify for early retirement. They must make a decision by April 16 and vacate their jobs by April 30. The offers were precipitated by a consolidation of USPS’ 67 districts into 50.