SB captain rotation. How long is each captain normally on board ?

[Isklaar]

Could anyone please help to solve a minor domestic dispute? When the captain joins the ship after time off, how long is he* usually on board for?

I was under the impression that it's 2 months. My 'better half' says 4 months. I believe the crew usually work 4 months onboard but not the captain. 

 

* Using 'he' because as far as I'm aware Seabourn currently only has male captains.I know that Regent has at least one captain who is a woman, but my question is specifically about Seabourn.

[SKP946]

According to the Captain on our last Seabourn cruise, Seabourn Captains work 70 days ON and (I think he said ) 70 days OFF.