BobKamman
Level 15

All I know is what Google AI tells me:

To officially gain U.S. expatriate status, a U.S. citizen must formally and voluntarily relinquish their citizenship before a consular official. This process is different from simply moving abroad, which does not end U.S. tax obligations. Long-term permanent residents must also take specific steps to terminate their legal residency.
The U.S. does not offer a temporary "expatriate status" for those living abroad. Instead, it defines an expatriate for legal purposes as a person who has formally surrendered their citizenship or permanent residency.

***

The exclusion for 2024 is $126,500, plus $37,950 for housing (varies by location).  So that's where he is coming up with ≈ $165,000.  Start with Form 2555 and its instructions.  After reading Pub 54.