If you read about Abp. Lefebvre's consecration on his official biography, you'll see that it was common knowledge that he was going to be consecrated a long time beforehand. He travelled to France to be consecrated on his own diocese, and, when he visited a monastery, he was bothered that the monks were already treating him with some priviledges, even before his consecration. There is even the term "bishop-elect". So, we can conclude that the Church's custom is to let everybody know some time before the consecration who was selected to become a bishop.
That being said, the SSPX deviates from Church custom on a lot of things, but I expect that they will publish the names at least some weeks beforehand.