Complex sentence: Beginning January 2012, ÍBV announced its plans to install 700 additional seats in time for the first game of the summer of 2012 against Breiðablik.
Split into simpler sentences: Beginning January 2012, ÍBV announced its plans for additional seats for 700 attendees. At the announcement, the estimated completion time had these ready for the first game of the summer of 2012 against Breiðablik.