This is going to be one of two things, but with really poor communication from the firm. I would really expect better, especially given you have asked them to update you a couple of times:
1) They have your application and video interview on hold. It is possible they have paused their recruitment or alternatively are waiting to see how other programmes/applicants get on before deciding on your application/candidacy.
2) They have made a decision on your application and have failed to communicate this to you. I suspect this is the more likely given the vacation scheme is in a month's time.
It is not to say that (1) isn't possible. I have worked in firms where they were making last minute decisions and conducting last minute recruitment processes/interviews to either backfill roles that have been reneged/declined, or where recruitment has been conducted exceptionally late due to lack of resource internally to do it earlier. However, given the timings, I suspect its unfortunately (2), which is just really poor recruitment standards and candidate engagement set by the firm (in my opinion!).