I am afraid that there is no remedy for "hardship" per se. The only thing that can be done is to file a Motion for a sentence modification.
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He needs a lawyer to help him file a motion, you can't file since you are not a party to the case. He should contact the lawyer who represented him earlier, or send a letter to the judge seeking modification of his sentence.
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He needs to either contact the attorney who represented him or file paperwork through the jail to return to court and modify his sentence. He can ask the judge to reduce his sentence or place him on house arrest. Unfortuately, there is no hardship relief for persons incarcerated. I wish you the best.