Submitted application 8/31, phone screen requested 9/16, had phone screening 9/20, transcripts requested 9/22, on-site interview requested 9/23, had on-site interview 10/17, references requested 10/18, job offer extended 10/28.
The phone screen was a half-hour phone call with one of the group leaders. They told me about Lincoln Laboratory and answered questions from me for the first 15-20 minutes, and then asked me questions for the remainder. The questions were about my background, my interest in the role, and my technical work experiences. They asked follow up questions when needed to get more detail and probe my understanding of the technical details.
The on-site interview was a half-day at Lincoln Laboratory, starting with two half-hour interviews with different group leaders. This was followed by an hour-long presentation of my PhD research, a 45-minute lunch interview with two people in the group, and another 45-minute interview with two other people in the group. I did not receive a detailed schedule in advance, but was guided throughout the day. It was very pleasant! It was around 50% me asking questions to get a better picture of the work, day-to-day, and group environment, and 50% me being asked questions about my technical experience and motivation. Overall great experience and got a positive impression of the group!