SoftBank Japan iPhone Premium for all IMEIs

iPhone SoftBank Japan Premium for all IMEIs 

How to check imei locked or unlock in this service

UNLOCKED -  Next Tether Policy Details: 2305 - Japan Softbank Blocked Policy
LOCKED - Next Tether Policy Details: 2079 - Japan Softbank Activation Policy
Service works ONLY on working days. Weekends and holidays are not included.