I had a military court martian and was returned to duty after fullfilling my court order punishment. I was then administratively discharged with a OTH.The discharge took 15 months due to my time in service.
There is a belief that an OTH can be upgraded after a few months its an urban myth--it IS possible but VERY unlikely.
Google "Discharge Review Boards" and go to the Army site and see the FAQ page.
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