Thanks again. I have read this on CIC wesite and understand that it doesnt apply on departure order if canada was left within 30 days. In my case i have departure certificate and ur suggestion is different from the text copied from the website below, 1. Departure Order (form number IMM 5238)
If you received a Departure Order and
left Canada within the required 30 days and
verified your departure with a Canadian immigration officer at the port of exit
you do not need an ARC. You may return to Canada subject to normal examination at the port of entry.