When it comes to finding synonyms for the phrase "leaping into breach," there are a variety of options that convey the same idea of courageously filling a gap or taking on a challenge. Some possible choices include "stepping up," "answering the call," "taking the reins," "filling the void," "seizing the opportunity," "rising to the occasion," "shouldering the responsibility," "embracing the challenge," and "meeting the demand." Whether you're talking about an individual stepping in to lead a team, a group of volunteers coming together to solve a problem, or any other situation where someone takes bold action, these synonyms all capture the spirit of leaping into breach.