The Emirates A380 flight to and from YYZ is always identified with the same flight numbers.
- Dubai to Pearson (arriving) is always EK 241 - also referred to as UAE 241
- Pearson to Dubai (departing) is always EK 242 - also referred to as UAE 242
These flights are (generally) scheduled for the same times on the same days each week, which are Monday, Wednesday and Friday. Arrival is usually somewhere between 3:00 and 4:00 PM on these days and departure will be around 10:00 PM the same day. That said; always check the status of a flight you are really interested in. The flight may be running late, early or even cancelled for that day. It's easy enough to check online and even setup a flight alert so you know if something changes.
Here's one of many ways to check on the flight (using flightstats.com). Just make sure you are looking at the correct date on the flight, since this link gives you a history of past flights as well. The one at the top is most likely the one you want to look at. Also, note that the flights sometimes don't become active too far in advance, so you're best off to check for the flight on the day it should be scheduled:
UAE241 - Arriving at YYZ
UAE242 - Departing from YYZ
I know this isn't the most complicated or detailed post I've ever posted, but hopefully it will be useful for someone out there!