Northrop Grumman interview questions

I got an email asking for an on site interview a few weeks in advance of the interview. the day of the interview I got another email asking if I could stay for a second interview right after my first. Apparently that was unusual, since after my first interview, which was fairly easy and mostly behavioral questions, the interviewers were confused why I was back in the waiting area. Apparently, one of their Cybersecurity guys saw my application and wanted to interview me separately from the standard interviews. That interview went very well, was fast-paced, and included some modest technical questions. I was told I'd hear back within 48 hours but ended up getting an offer 10 days later with a phone call.