While the Clan War search is ongoing, Co-Leaders or Leaders can cancel the war search at any time, but once a match is found, canceling the war can no longer be done and the war enters its preparation day.
The bonus can be increased by winning attacks, but most of it is lost if your clan loses the war. Bonus loot is your prize for winning the war. Each epic 47 hour event (23 hour preparation + 24 hour battle day) is won by the clan who scores more stars.
