Hey Octet,
Former I.B. student here now in first year of iSci. If you get in you might be a minority in your year; only 3 out of our 54 this year were from IB.
I, like you, couldn't take IB Higher Physics so I took grade 12 physics after the summer of grade 10. Looking back, I would recommend you take it this summer to refresh your memory. The prof moves at a fairly quick pace and speeding through new material can be challenging.
I definitely don't think the material you learn in IB is "irrelevant". For example : If you did Option G chemistry, you'll find the Orgo in first year easier to grasp, and you'll have basic understanding of the details in the second year course (There was a take the first years to an upper year class concentration day and the prof blazed through a chunk of the syllabus in an hour). Besides if you're intuitive, you'll find ways to apply your knowledge in some pretty unexpected ways.
Hope this helps, and as for the app and its fate, may the odds be ever in your favour.
Doug