Reviewing the link you sent me, my sister is category F1 and it shows that cases from Nov 2015 are being processed.
However, for the legal residents cases from May 22, 2016 are being processed. I thought that citizens got priority, obviously no. It saddened me because my mother is sick and 87 year old. Idon't know if she can wait a few more years to see my sister here with her.
I really appreciate your response.
Thank you