The order are not able to travel back in time, but they have found a way to freeze time for up to 5 seconds and this has allowed them to do all kinds of things in present time that have shaped the way in which millions of human decisions have been made. They can do up to ten of those five second time stops every 300 hours. They have been able to steal documents, abduct humans that seem to disappear out of thin air and destroyed research that could lead to problematic situations.
The order are looking for ways to find larger portals to freeze time and this is going to make it easy for them to perform other alterations that can help stop all sorts of terrible catastrophic events. The time freeze is the closest the order has been able to get to time traveling.