According to the BeeDictionary, "circle around" means to move around in a circular motion. That does imply redundancy or endlessness doesn't it?
In the case of your boss saying "with", it kinds of changes the meaning a bit. It implies that you are the one doing the circling around, and that the boss will join you in your circuit later on (hence, the "catch-up" meaning).
By "circling around" the boss doesn't mean endless or pointless wandering, but rather he means by what you do everyday, your normal tasks and jobs or errands etc. Thus, he would join you later in order to catch up with you.