If it's likely you'll need layoffs, it's probably best to move as quickly as possible. Otherwise gossip, speculation, and fear have the chance to dominate.
Just in case you didn't recognize the reference - an early Facebook cultural motto is the phrase "move fast and break things" - a tradeoff favoring product development iteration speed over stable infrastructure.
Facebook would then change their motto in 2014 to "move fast with stable infrastructure" [0] - don't know how well that's worked out for them since.
