It is still possible to inject backup in your iphone to remove icloud with FMI ON using backup – ios 9.3.1
Download backup https://myicloud.info
You can upgrade via OTA only (Over the air) old icloud will still be ON in APPLE icloud activation servers.
Remove icloud from ios 9.3.1 on activated Iphone, ipad , ipod
All icloud unlock methods here:
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