Systems, devices and methods for sorting items

Sorting systems and methods for large quantities of items in industrial processes are described. The systems, devices and methods are for receiving, sorting and removing items dynamically. A first group of items, such as letters or other mail pieces, are injected by a belt into a pocket to a form a first stack, and a divider is extended near the first stack. The divider allows for a second group of items to either be injected to form a second stack behind the divider, or to be diverted and injected into another pocket. The first stack can be removed while the second group is being injected.