Johnny's presents Hey! Say! JUMP LIVE 2019 in Taipei will take place on 5th & 6th Oct at Taipei Arena
https://www.j-storm.co.jp/heysayjump/news/7442
That would explain why some of the HSJ members are currently in Taiwan
My Taiwanese friends who're in HSJ fanclub are considering to attend even though they're now based in Japan xD
Guess Japan's loss of an Arena HSJ tour this year is Taiwan's gain