HADT reads cleanly across the Americas in this dataset, but the same letters can mean different things elsewhere (notably CST, EST, and IST overlap with non-American labels). Pin the IANA zone when the audience is international.
America/Adak has an upcoming offset change on November 1, 2026. After that point, HADT on this page will read a different UTC offset until the next transition, so any saved timestamp should anchor to the IANA zone rather than the abbreviation.
For precise work, the safest equivalent of HADT is the exact IANA zone used by your city or system. America/Adak sits at -09:00, behind UTC, which means daily logs in this zone reach a new calendar date after UTC does — relevant for date-aligned reports and billing cutoffs.
Within this single zone (America/Adak, -09:00), HADT is unambiguous, so the abbreviation and the IANA zone effectively interchange.