She will get 25 percent off of her time sentenced plus credit for any time served. Electronic monitoring will be coming back to Milwaukee, and she should ask or see if she can get her sentenced amended so that she is eligible.
This is not intended as legal advice. It is only provided for educational purposes and cannot be relied upon as legal advice. Further no attorney client relationship is or has been formed by answering this question.
Goodtime credit is common so the information you are getting sounds credible. You can also contact the county jail and ask them about their good time policies. Good luck.