An
article in Friday's WashPost about when (oh, when) a new owner for the Nats will be named says that the city expects "Major League Baseball to name a new owner of the Washington Nationals in time for
Thursday's groundbreaking for a $611 million stadium project" (emphasis mine). That would be Thursday, May 4 for those of you counting along. No mention of a time or anything, I'll keep digging. It also says (and this makes sense) that the groundbreaking is the day after the financing bonds are to be sold on Wall Street.
UPDATE: I hear through the grapevine that this will be at 10 am.