He began his sentence Friday night and will be released on July 9. The Jets begin training camp July 26. Ellis would have to complete his sentence starting March 1.
He was originally scheduled to serve out his term until July 29, missing the first three days of camp.
Jets coach Rex Ryan said Ellis should be ready to make significant improvements after making just seven tackles as a rookie last year.
"I think he's a strong man, and I know one thing -- he's looking forward to this season," Ryan said.
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