Lawyers say the accelerated schedule is resulting in some children, some as young as 4 years old, appearing in immigration hearings without legal counsel.
In one instance, a hearing scheduled for 2027 was suddenly rescheduled for less than a week away.
The White House argues the changes are intended to get children home as quickly as possible. A Department of Homeland Security official says that reducing time in custody also means less cost to taxpayers.
As of March, more than 2,000 migrant children were in U.S. custody. On average, they spend about seven months in custody. far exceeding previous timelines.
CNN contributed to this report.