I'm currently in my first year of the MSc. S-LP program at the U of A. Regarding your first question, I had one course in progress at the time of the application deadline. Last year, people started getting early acceptances before I even finished that course. I was notified I was on the waitlist in March and received acceptance in April. Regarding your second question, I believe the expiry date is 10 years, but you should ask someone at the admissions office! I was a career changer - I worked in a different field for a few years before pursuing S-LP.
Let me know if you have any additional questions!