Catherine,
You will be sworn in and appointed OCdt and paid at that rate (monthly alloted bi-weekly) approx 1273/Month less rations and quarters and other good old mandatory deductions CPP/QPP (thats right QPP for the time you are in Que) and son on, upon completion of whichever Phase DEO Candidates are commissioned (I'm honestly not too sure if its the end of IAP/BOTC as CEOTP applicants or different for some reason) you will be commisoned 2lt and paid as a 2lt and backpaid from the day you swear in (if it states the effective date of commsioning to be your swearing in date on the offer/msg) I am assuming you have no previous service so you would be paid as 2Lt Cat C pay incentive 0, if however you do have previous service in the rank of Cpl or above you will be paid as 2Lt Cat D IPC 0, I could be of the mark a little as our situations a different but CBI 204.211 (linked below) Refers, feel free to pm me if some of this is unclear.
John
http://www.dnd.ca/dgcb/cbi/engraph/home_e.asp?sidesection=6&Section=204.211&sidecat=21&Chapter=204#204.211