I just got approved today but me and my husband applied at the same time and he hasnt got approved yet.. so I guess it depends on our case workers.. but i was in the boat as you I thought i was never going to get approved and today i just went to the website and there it was.
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App Sent: 10/19/12 App del: 10/22/12
G1145 Notice : 10/26/2012 I797c: 10/29/12
Biometrics Letter : 10/31/12 A ppt: 11/27/12 No walk-in
Approved: 02/05/13 Letters of Approval: 02/07/13