Will all $ owed from earning be deducted from a single check?

My 19 year old goddaughter is on SSI. If she makes $485 in a month she keeps the first $85 and they would take half, $200 of what is left.

The question is, would they take that entire $200 out of the next check after reporting? I have heard that you can make arrangements to have only 10% taken out at a time, but is that only for back payments?

She still owes back pay from last winter that SS failed to deduct after we had reported it and so they are deducting it now. So we wondered if they would deduct back monies owed as well as the total based on what she earned this month.

Thanks for any answers.