Thanks saxo. You are an expert on the whole application process.
Another question:
If I apply for Prelim and categorical position in IM together then I am only charged fee for one program ( as both are in same program).
I am not clear what happens if I apply only for categorical position now and maybe later apply for Prelim position at the same program.
Is it possible to apply separately (for Prelim and categorical position) at the same program and if it is possible then will I be charged twice or only once?
I am not an expert buddy, we are in the same boat

Yes, you will be charged for both preliminary and categorical separately. You can apply to each of them when you want to. Usually, people avoid applying to both preliminary and categorical at the same program because that would be like sending mixed messages to the program about your interests.