ACC - Lilac Corporation purchased 25%of the Coffee Corporation stock outstanding

On July 20, 2012, Lilac Corporation purchased 25%of the Coffee Corporation stock outstanding. Lilac Corporation purchased an additional 40%of the stock in Coffee on March 22, 2013, and an additional 20%on May 2, 2013.On September 23, 2013, Lilac Corporation purchased the remaining 15% of Coffee Corporation stock outstanding. For purposes of the §338 election, on what date does a qualified stock purchase occur? What is the due date for making the§338 election?