I found this:

http://history.amedd.army.mil/booksd.../EPWs/EPWs.htm

Search for text 'overhead' on the page and find this:

Planned capacity of Central Prisoner of War Enclosures in France.— Even at the beginning, Central Prisoner of War Enclosures were too few, too small, and understaffed. This led to overcrowding (fig. 34) and impeded the application of preventive medicine measures as well as the processing and handling of prisoners. The following report and comments give information about the deficient planning and its consequences.


Theater planning for the handling of enemy prisoners of war was rather unrealistic. It left much to be desired and apparently ignored the difficulty experienced in North Africa in handling a large influx of POW's. This cannot be completely laid to inadequacies in the Theater Provost Marshal's Office which was planning within the restrictions imposed by the overall concept of the operation. For instance, the planners asked for 49 Military Police Escort Guard Companies; only 19 were authorized by the War Department. As there was no T/O&E for a Prisoner of War Camp Overhead Detachment, the Theater Provost Marshal planned a provisional one and got authority to activate eight of them, one for a POW camp in England and seven for use in France. Each of these POW Camp Overhead Detachments was estimated by the planners to be able to handle 6,000 POW's. Thus the planning was geared to accommodate at any one time a total of 48,000 POW' in the eight camps. The capture rate for the first 90 days was estimated at 1,000 a day. This would require that about one-half of the number captured during the first 90 days would have to be shipped out of the theater.

I have suspicions that they were small, temporary MP units formed to guard POWs in the ComZ who were in transit camps in route to permanent camps in England or CONUS or possibly overflow camps for these transit camps.

On down on the page, there is interesting reading on my country's mistreatment of German PoWs.

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Best Regards,
JW