No. The new USCIS policy memo does not automatically mean that every person applying for a green card must leave the United States.
USCIS recently issued a policy memo describing adjustment of status as a discretionary benefit and suggesting that, in some cases, applicants may be expected to pursue consular processing outside the United States. This caused a great deal of confusion and concern for many applicants.
However, the law has not changed. Adjustment of status is still available under INA § 245 for applicants who are eligible to apply from inside the United States. USCIS may now apply greater scrutiny and look more closely at discretionary factors, but eligible applicants may still continue to file for adjustment of status in the United States.
Every case is different. Some applicants should file for adjustment of status in the United States. Others may need to consular process through a U.S. Embassy or Consulate abroad. But leaving the United States without proper legal advice can be risky, especially for individuals who have unlawful presence, prior immigration violations, criminal issues, or other inadmissibility concerns.
If you are not eligible to adjust status in the United States, consular processing may be the proper option. However, before leaving the United States, you should speak with an experienced immigration attorney to determine whether you need a waiver, such as Form I-601A, Provisional Unlawful Presence Waiver.
Do not assume you must leave the United States just because of headlines or social media posts. The correct strategy depends on your immigration history, manner of entry, family or employment petition, unlawful presence, criminal history, and whether a waiver is required.
Before making any decision, consult with an immigration attorney who can review your specific case and advise you on the safest path forward.

