Last year they were announced late May/early June; I remember it, because reading the list of the skaters assigned to Skate America was the final decision maker on me going to the event. So, I think we'll be seeing them in the next week or two.
USFSA (sorry, I still can't get over myself and call it US Figure Skating) said that they will be announcing the assignments in June. "Early June," I think they said. Aka SOON. I don't know if we'll hear assignments for the international skaters at the same time. I hope so...I am getting so impatient!!!