Complex sentence: The building has been occupied since 2003 by the Jugnauth Couple, that is Sir Anerood Jugnauth and Lady Sarojini Jugnauth as their mandate started in October 2003 and they are due to leave the Old Mansion in 2013.
Split into simpler sentences: The building has been occupied by Sir Anerood Jugnauth and Lady Sarojini Jugnauth since 2003. They are due to leave the Old Mansion in 2013.