No, as Bambiegirl said it won't affect your application as long as they're not your prospective employers in Canada. 12:30 is too much if you start early. Find a new employer from there so you can still legally stay in HK. Tough but you should not take crap from them if they abuse you. Are there organizations there that can help you in case they make life miserable for you if you broke your contract with them. Keep a log or time sheet of what you do to prove your work hours.
YES...now that they know that my papers is in process they are abusing me...my duty now to them till 12.30 midnite sometimes till 1 am...i want to break my contract to them but if thinking it my affect my application...