@Anonymous
1. I am missing something here -- dual status and first year choice do not compute. It is one or the other for the year
2. Ideally you do not want to update W-2 -- ask your employer to issue you a W-2c --- because IRS will generally go by the copy they have received from the employer.
3. Generally, your employer is responsible for part of the FICA contribution and cannot arbitrarily do a lump-sum ( if that is what you mean ) contribution in the following year.
4. For all of the above reasons we really need more detail of the situation-->
when did you come into the country first and what visa; are you married and if so to another NRA or resident or citizen or ?; which country are you from; what type of work did you do in 2020 and was this your first year of work; how did you file for 2019 ? anything else ?
Also note that TurboTax does not support diual status filings even though one can definitely use TurboTax to do the 1040 and do the 1040-NR by hand and submit by mail.
stay safe
