What is the name of the first time zone to reach New Year's Day, at UTC+14?

The first time zone to reach New Year's Day at UTC+14 is Line Islands Time.

Line Islands Time, abbreviated LINT, is the time standard used in Kiribati's Line Islands. Its UTC+14 offset places the islands on the earliest civil calendar date used anywhere in the world. Kiritimati, also called Christmas Island, is the best-known inhabited place in this zone.

Kiribati moved the International Date Line east of its eastern islands in 1994, aligning the country's scattered islands more closely on the same calendar day. As a result, the Line Islands became famous for being among the first inhabited places to welcome a new year.

UTC+14 does not mean that the Line Islands are always the first geographic locations to see sunrise; sunrise and celebration timing depend on longitude, season, and local conditions. The precise answer requested here is the time zone, not Kiritimati or Kiribati.