Permanent Allocation changes to Free-For-All

My friends and I play together quite frequently. Each of us has the UI option for Allocation type set to Permanent. Normally this works fine. We can run maps all the time with it and it isn't a problem. Once or twice a week, however, we will zone in to a map (or a safe house) and shortly notice that the allocation has changed to Free-For-All. Not just an item or two, but in the upper right corner of the screen it will actually say "Free-For-All". It isn't just an error in the labeling either. Loot will be Free-For-All (and we are not off-screening or out of range for it). After we get through that map, it is more likely than not that the next will be just fine and back to Permanent allocation.

This has happened regardless of who is leading the party. I have not noticed any pattern that is causing this behavior.