HappyCelery1441 currently there is no mandatory requirement to continue the course for 5 yrs. If you extend your stay at immigration you need to show current enrollment in a course. You are better off doing Workcation if you can.
Tokyo is extremely focused on justification to give a 5 year visa and often give a 6mth visa. Your TV is for 6mths and will enable you stay around 8mths if you time your final entry correct. You can apply elsewhere in SE Asia once your TV ends. Other Japanese applicants did that and one posted about it last year, their post should be in the threads. I do not think anyone has made an appeal. Osaka and Fukuoka are easier to get DTV approval and i know Tokyo residents who chose to apply there and got approved.
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