Your situation is not an uncommon one. For almost all major consulting firms, MBB and non-MBB, campus recruiting is a well oiled machine with predictable and consistent annual recruiting cycles that allow internal firm recruiters to line up the appropriate number of resources for first and final round interviews (with extras to account for interviewer cancellations). The recruiters have the luxury of being able to pick from a wide pool of Associates / Consultants and Project Leaders / Managers for first round interviews and Associate Partners / Principals and Partners for final rounds. After all, they are interviewing generalists. So, any firm member can be an interviewer.

When interviewing for Experienced Hires, specific firm members conduct the interviews that are associated with the role (e.g., practice members), at least most of the interviews. This means the interviewer pool can be quite small. In your case, which is not uncommon, it sounds like at least one or more of the interviewers had a conflict for the upcoming weeks after the first day of interviewing was cancelled. Since MBB firms don’t usually like to bring candidates in for one interview at a time, they are likely waiting until the entire set of interviewer’s calendars line up.

I’m a little surprised they haven’t brought you in for the informational interview. Also, I would have expected them to keep in reasonable contact (every 7-10 business days with you) but you don’t mention whether or not they have done that or not. If they have not reached out in over 3 weeks and especially 4, you should definitely reach back out to understand what the status is. I hope that helps but ask any follow-up questions in the Comments.