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... A copy of Form I-797, Notice of Action, showing that USCIS approved you for U nonimmigrant status,
A ... has never held U status, you may apply for immigration benefits for them after you receive a receipt notice ... Filing Adjustment Application With USCIS
After you file Form I-485, you should first receive a receipt notice ... , and later, a biometrics appointment notice where you will have your photograph, fingerprints, and signature ...