As pehoeji and tailo variant subtags were added to Language Subtag Registry on March 4, 2024 [1],
we should now use recognized BCP 47 subtags instead of private -x-* subtags (for example, [2] ).
- nan-x-Q56929 => nan-latn-tailo
- nan-x-Q559173 => nan-latn-pehoeji
[1] https://www.iana.org/assignments/language-subtag-registry/language-subtag-registry