I'm currently a student of SIT Acc. I would say that it is definitely hard to get into Accountancy every year since the course commenced. The first year (pioneer) batch was easier to get in because there are still many many people who doesn't know SIT accountancy exists. (probably never read the news or not enough marketing) So every year, the requirements will be more stringent, especially I heard from my Profs that thousands have applied but the course is only opened up to 100+ people.
Based from what i heard from my coursemates, non-relevant diploma (yes, even banking & finance are considered non-related) applicants will need to have higher grades to get in. So the people I know usually got (3.7 to 3.9). And in teh interview, 90% the interviewer will ask why you wana switch ur field to accountancy especially if your diploma is like totally not related.(science, engineering etc.) Better to come up with a convincing reason why you wana try accountancy this time and not continue your field from poly. As i recall, they open abit lesser spaces for non-dip related, but im not sure this time because they may expand the intake.
For related dip holders, the lowest gpa I've seen that got into this course is around 3.4? But if take into account of more applicants and grades inflation, I can tell you that even those people with 3.5 will have a tough competition this time.
And the interview last year I heard was tougher than the pioneer batch interview. So good luck... and to end off, this course is not easy, even if you're from accoutancy background. But if you can manage your time well in the squeezy hectic fast paced trimester, you stand a chance to get first class.