Immigration Site

My Mother was a greencard holder, on september 2001 she applied for me ( unmarried son - under 21 )
then i turn 21 and my mother got US citizen 2years ago and my case is changed i think
We received the approval notice on January 7,2009 and after that i received a letter from national visa center that include my case number start with ANK******** ( i think its ankara-turkey) and tells me to wait till visa number is available

we send my mothers citizenship notice to NVC 2years ago and they send back a letter that they received it.
when my mother applied for me i was 17 and im sure it was september 2001
when i turn 21 i think my case changed and when my mother became a us citizen the case is changed again..

how long i have to wait until i receives my visa considering ?

i live in iran and sorry for my poor english
Thanks for helping me out.

You have to wait for your PD to become current. Once its current, NVC will contact you for your case processing. I am not sure about your GC time frame as it varies from country to country. Ive heard anywhere from six to eight months to a year.
Good Luck!

Do you know how to check the Visa Bulletin?

thanks citi786

yes i just checked upcoming months visa bulletin: September 2010
its on 01JAN06 for 1st FAMILY-SPONSORED PREFERENCES

we call NVC and they said my case was approved on FEB 2008
i checked Archived visa bulletins and i notice that they process 4 months each month .. am i right ?
01JAN06 > FEB08 ( 2 years = 24 months ) so if im right they can process 24 month in 6 month ( 4 months each month )
so my visa will be available 6 month from september..

am i right ?