I'm not sure what the frequency is now, but when I was in, the carriers were rotated after six months. And your ship did not turn for home until it was relieved. I don't know how many of these "Oh my God were going to war with Iran" stories I've read here because of Carriers leaving the U.S. for the Gulf.
I think it happened the same week last summer. I remember because I’m at the beach this week.