State residency for boarding school students

[sybbie719]

linking a previous thread

Boarding students and National Merit designations

What state do boarding students use to determine the index score that applies to them - their home state or the state that their school is in? Is it still true that semifinalist and finalist levels are determined within a special boarding school pool, rather than the state?

Thanks to @skieurope , who previously answered this question

By the boarding school region. So all students at a New England BS will need to hit the level of the state with the highest score amongst the 6 states, which is typically Massachusetts.