In iTunes sync-option, "replace information on this iPhone" with the explanation: "During the next synch only, iTunes will replace selected information on this iPhone with information from this computer." How selected? Most recent on either?

For reasons not worth explaining, Since the last sync, I have updates to some of the same contacts and calander events on both my iPhone and Windows computer with Outlook. I want to sync the two devices now and I hope take the most recent version from either device. If I select to replace information on the iPhone from the computer, does it only select the most recent information? Does it copy to each device if both were changed since last sync?