junglie
From what occured last year there were a few who joined as 330 only, but shortly got put on Mixed fleet at their designated base. I don't know when their CCQ courses where scheduled though, that will depend on when TCX can fit them in.
I would expect to join as 330 only, to be then given the A321 CCQ at some point and remain MFF until your 330 only seniority bid is accepted.
If you join with a valid TR (330/321/even 757) I would expect a perm contract. Last year the only people without perm contracts were the cadets who got a 7/5 contract for the year.