I used VJW today for my upcoming trip, arriving in Tokyo on 13 Nov.

I previously did MySOS for a previous trip in Oct, and I forgot to clear my phone browser cache first before starting a new submission for the quarantine stuff. Spent awhile wondering why it wouldn't save the questionnaire. Once I sorted that out, all good and it only took about 5min for my vaccination cert to be reviewed and the quarantine procedures page turned blue.