I am EB2 Rest of world. I-140 approved in October 2008. PD August 2008 concurrent filing. Called on for interview in March 09, 2009.

ISSUE:
I came as a F1 in 1992 but did not go to school. Immigrated to Canada in January 1996. Refused admission at Niagara Falls later in June 1996. Got Canadian Citizenship in 1999. Came to USA in 2001. I travelled 4/5 time out of USA in last 5 years. Every time they ask me about that refusal and after delay they let me in every time.
QUESTION:
1) My out of status happened well before April 1, 1997 and I have all the proof that I resided in Canada until 2001. Do you think it may be the issue in interview?
2) I got my interview notice 3 week ago. My wife and son (19) did not receive notice. is it normal?