I see that no one is venturing an answer. The issue became stranger. In one instance when I inserted a figure, the figure caption had the right margins and the split paragraph where the figure was inserted had the lower or split text with the correct margins, but the following paragraph reverted to the mismatched and non-mirrored margins. I see no control such as a section break at that point. Again, every page...with and without the proper mirroring shows the same settings but for some reason those setting for the mirror margin are being overridden somehow. The margin is 1 cm too wide everywhere the mirroring is not working properly.

Hope this helps jog someone's memory.