When you arrive in Vancouver (Day 4) the ship will be cleared by CBSA, the gangway will be opened for you to go ashore you're free to do whatever you want.... Welcome to Canada! Why you couldn't walk off the ship at 0500 with your bag on Day 5 and make your way to the airport is beyond me; you're not a captive. However, you probably should check with NCL Customer Care beforehand just in case there is some bizarre reason you can't (good luck with that phone call). After all, you could walk off the ship with your luggage at noon on day 4 and never come back.... they can't stop you.