A typo was made when the Pacific timezone Truk was removed and replaced with Chuuk. A backwards compatible link was maintained with Truk. The new shorthand ID for Chuuk is CHUT (non DST mode) - for the ja locale resource file, "HUT" was put in as a typo. The consequences are minor (wrong shorthand representation of Chuuk returned for Japanese locale but the long display name will still work correctly.)
The tzdata change for Truk->Chuuk was immediate. i.e. it's a direct substitute with no crossover timeline involved.
Should be fixed in next available release.