Depending exactly on what you are referring to, this could have been an AP vs Chicago thing. Neither is wrong (or correct) in a vacuum, but, your editors should

Depending exactly on what you are referring to, this could have been an AP vs Chicago thing. Neither is wrong (or correct) in a vacuum, but, your editors should pick one style guide and adhere to it. Hopefully they will point you towards the style guide when you have disagreement over a correction instead of keeping you guessing, of course.