Probably nothing. If she already has counsel, the lawyer could ask for a probation bond, but they'll probably not be inclined to give it to her and it's unorthodox to do so. As for the punishment, it depends on the nature of the violation (general violation or special violation?) and the recommendation from the probation officer. Also, how to handle her case depends on the merits of the violation.
The lawyer can speak with the jail solicitor to try and get the case on a calendar in the next few days and can speak with the PO to try and seek a favorable reccommendation. While the attorney may not have any official powers to speed things up, they CAN use soft skills to make things happen.
I agree that there is little an attorney could do to get this person out of jail sooner. In this situation the best attorney is probably one that practices frequently in the arresting jurisdiction. There are situations were an attorney can get a probation bond or the hearing moved sooner. This would involve being familiar with the judge, prosecutor, and probation officer. Also, the nature of the original charges and the reason for the probation violation warrant, would factor into the person's release date.