If he is chosing Piano/Music education then his skills at the piano do not have to be as high as if he wanted to study peformance of course. It all depends on the school though. I advise any of my students who want to studying music at univeristy or a music school to commit themselves to their study at least 3-4 hours a day, memorising new stuff (musically and theoretically).
I don't think the goals are realistic that he will be able to improve his ability by a huge amount in 8 months even with intense study and a 6 year gap between his previous piano studies. A good teacher may reduce the time needed but I would say 2 years sounds more realistic to see changes. It also depends on the individual and how much effort is put in. If he is developing while being examined by the university he might be dissapointed with his results.
I am the type of person who if I do anything I want to do it the best I can and do it right even if it takes extra time. But some people like to "just" pass, and just get through, do things faster so you can do more, learn from errors. I wonder if it would hurt him to deffer his studies for a year, concerntrate on his piano and theory and then go back to the uni and take up music. He would be very prepared then, there is no rush with music.
If one graduate from music at 26 or 32 it makes no difference in my mind. Its not like being an..... accountant, you want to get out there and climb to the top of the business pyramid as early and as fast as you can. I guess if you want to become the head of a music university then you want to go and graduate as fast as you can and get working, but the majority of musical graduates will be self employed or work for a school with little movement in career postion. If you want to become a peformer you have to present a peformance that the audience didn't know they needed and make your career from that.
Music is not like any other subject, 1+1 doesn't equal 2 in music, but anything so long you make it right in your mind. It is the same as being a writer, so many different ways to write a book, there is great difference between the writers in this world but they all are great in different ways for the individual. Music is the same, how you do one thing this person will appreciate, but at the same time the next person will be totally the opposite. In the end you have to be satisfied with what you are doing musically, no one will show you what to do, they can suggest but in the end you must make decisions yourself. This might be also another reason why he should deffer his studies before taking up music, so that he knows where he really stands musically. Studying music full time is VERY VERY different to studying 1 hour a day. He may even hate it as a lot of my students who have a fantasy of becoming a musician found out and quickly ran back to "real" life.
The subjectiveness of music can get a lot of people into strife, especially in the peformance side of piano and learning concepts for the first time. So usually it is a good idea to first teach yourself a lot of the stuff you will learn at the school, then when it is discussed/lectured in your tutorials/lectures, you will not be new to the concepts and will be able to observe other ways to understand the same thing.