Board Thread:Questions and Answers/@comment-31734215-20170609063230/@comment-26322848-20170609090231

Oh, I see! Normally, they send an announcement on the second-to-last day of an event to remind people what time it's over. The "bonus" part is about remembering to take out the event rewards (aka point/rank bonus), because people sometimes wait until after the event ends to collect the sports drinks and yakisoba breads so that they last in the present box longer.