How long did the Japan-Okinawa Mission continue?
Until March 18, 1970. That was the day that the two Japanese missions became four: the Japan Central (Kobe) and Japan West (Fukuoka) Missions were created from the Japan-Okinawa Mission. The Japan (Tokyo) and Japan East (Sapporo) Missions were created from the original Japan Mission. Also that month, the Tokyo Stake–the first in Japan–was organized, on March 15, 1970. Two days earlier, on Friday the Thirteenth, the Mormon Pavilion was dedicated at EXPO ’70 in Osaka.