You must a currently dated letter from your intended permanent employer, describing your present job duties and position in the organization, your preferred position (if different from your current one), the date you began employment and the offered salary or wage. This letter should be in the original and signed by an executive or officer of the organization who is authorized to make or confirm an offer of permanent employment. The letter must also indicate whether the terms and conditions of your employment-based visa petition (or labor certification) continue to exist.
"The letter must also indicate whether the terms and conditions of your employment-based visa petition (or labor certification) continue to exist.
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what does that mean?