Complex sentence: It was announced in early May 2008 that Atomic Jam would return to the venue in the last quarter of that year, and the 13th birthday event was held on 22 November 2008, and another event was held on 7 March 2009.
Split into simpler sentences: It was announced in early May 2008 that Atomic Jam would return to the venue in the last quarter of this year. The 13th birthday event was held on 22 November 2008, and another event was held on 7 March 2009.