The superintendent, James Groff, said the Defense Department directed the Military Postal Service Agency in May to end service for those customers.

"There's other retirees that are affected all over the place," Groff told the publication.

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The news has sparked outrage among military retirees living overseas, as they would need to rely on international mail for crucial correspondence, including voting ballots, Department of Veterans Affairs claims and checks, and tax submissions and returns.

They also would lose access to medications through Tricare's mail-order pharmacy program, which does not ship to international addresses.

"It would affect retirees a lot. If you don't have access to FPO, there's a high likelihood that mail will get lost in the [international] system," said Mike Applegate, a retired Navy chief petty officer who lives in the Philippines. "I don't want to offend anyone, but the postal system here isn't the greatest. I remember one time it took me six months to get something."

"I hope it doesn't happen," said Wylie Miller, a Navy and Air Force veteran in Naples, Italy. "I volunteer with the retiree community, and there are 37 widows over here who depend on it to get their survivor benefit checks, tax refunds, their medicine. I worry about this group."

Retirees said they were especially alarmed by a memo circulating in the Pacific Region, allegedly to military postal superintendents from the Military Postal Service Agency that tells them to "stand by" for "further guidance on notification and termination procedures (at the appropriate time) for those individuals and or organizations no longer authorized MPS privileges."

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"Some examples of individuals and organizations who will lose access include military retirees, enemy prisoners of war, Red Cross, foreign military individuals and units, U.S. citizen NATO Direct Hire, banks, university and other government agencies," the memo states.

In response to questions from Military.com, the DoD provided a statement attributed only to "DoD officials."

In addition to determining that some users were barred from using the system under host nation agreements, Pentagon officials said at least seven of the 21 formerly authorized patron groups lacked "established fiscal authority" to have access to the system, which allows most patrons to send and receive mail at domestic rates through FPO and APO mailboxes.

The Defense Department did not answer specific questions on who is slated to lose access, nor did it respond to a question for clarification on the seven groups found to lack fiscal authority to use the mail system.

But the DoD added, however, that the issue is still being debated.

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"The Department is reviewing this matter and is sensitive to addressing the needs of current [Military Postal Service] patrons in a timely manner," the statement read.

The Military Postal Service Agency was created in 1980 to consolidate the mail systems of the individual military services. It provides mail support in 63 countries through 401 land-based post offices and 626 based on ships, according to the U.S. Postal Service.

By law, it provides mail services to active-duty personnel and their family members, DoD civilian employees and their families, and U.S. military contractors. Other groups authorized to use it, depending on agreements with host countries, include retirees, non-governmental organizations like the American Red Cross and USO, banks that serve U.S. service members, American crews of Military Sealift Command, surviving family members and others, according to the previous manual governing the agency, which was canceled by the May 24 update.

Under the new revision, the only eligible patrons are "individuals authorized to use MPSA postal services and mail program within and outside the United States, consistent with international agreements; laws; and Federal, USPS, GSA, and DoD regulations."

Retiree groups have taken this to mean it doesn't include them and are urging expats to contact their elected officials to protest the move.

"The impact this will have on the non-[Status of Forces Agreement] military retiree and widow population is enormous," wrote the 8th Army Retiree Council in South Korea to members.

Still others believe it will not come to pass. In a message posted on a military health care Facebook page, Erik Thomsen, the casualty manager and post-retirement services officer at U.S. Army Garrison Rheinland-Pfalz, said the rumor that retirees are getting the boot is "ABSOLUTELY NOT TRUE."

"There was a misunderstanding in reference to a DOD Directive and the rumor was hatched," Thomsen wrote. "You will still continue to receive your mail. If you have further questions, please do not hesitate to call our office."

Thomsen did not respond to a request for clarification by publication.

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Applegate said retirees should be exempt from any changes, given that they are subject to recall to the armed services during national emergencies.

While he noted that while the possibility was remote, it is the law.

"I'm 69 years old. They probably won't send me, but it's something to consider. We're offended that we're subject to recall and they are doing this to us," Applegate said.