The US Embassy in Armenia has published information regarding the US immigrant visas..

“When you become a U.S. citizen, you must submit proof of citizenship to the National Visa Center (NVC) so they can update your family member’s visa category.  The spouse’s case may convert from F2A to IR1/CR1 (immediate relative). Because immediate relative visas are not subject to annual numerical limits, this reclassification can reduce the overall waiting time,” the embassy noted. 

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