1. Been averaging 40ish a month on reserve (but being told that will dramatically increase starting in about 3 weeks).
2. No, not dual qualled, and so far not being told of any plans to dual qual us (would be nice, though).
3. No idea on percentages, but on reserve in April, I never left the Kingdom, had a line in May, so had 2 Int'l trips scheduled, and back on reserve in June, so who knows. But, as a reserve, expect a lot of domestic trips. (I seem to be drawn to Abha multiple times a day...)
4. No idea about interviews now. Last year, they were 2 part interviews -- first part was one day in Cairo (written test in the AM, interview in the PM). Then a month later, back to JED for sim and medical. The written was almost word for word from Acing the Airline Technical Interview (or something like that). Again, not sure if that is still the format today, but it was a straight-forward, relaxed, non-confrontational process.
Good luck, hope that helps.