I don't think that applicant has gone to the interview yet, HKVO has been sending out interview emails like crazy, just recently there are at least 30 applicants from October, November and December have to do interview later this month or in November, and their ecas changed to IP either the same day they got the interview email or a few days after, anyways, all of the applicants' ecas are IP but still have to go to interview (also a lot of them have the medical results received shown as well)
Due to seeing those applicants' cases, I'm not quite sure how my VO works.......although my ecas finally shows IP on the 9th this month, I have doubts that HKVO just updated the system to the new IP so even though I'm a March applicant but this IP I just got might be the new one :/ Just my guess.