difference in two tax depreciation areas

I have two tax depreciation areas that were fully depreciated at data migration. They both have the same useful life, same expired life, and same depreciation key.

I made several partial retirements to the asset affecting both depreciation areas this year. One depreciation are shows some of the retired accumulated depreciation as a value adjustment for prior year depreciation and some as ordinary depreciation.

The other depreciation area shows all of the retired accumulated depreciation as a value adjustment.

Why would the one area show some as ordinary when everything is the same and there have been no other transactions since migration. I should mention that the asset was acquired in 1992 with a 7 year useful life.