Allocation orders can be used to do for example a switch on an account. A number of sell orders can be mapped to an allocation of purchases of one or more assets.
Example:
On an account a switch shall be made from asset 1 and 2 and distributed beteween asset 3 (30%) and 4 (70%). Sellorders are created for asset 1 and 2 and when these orders are finished buyorders are created according to the new allocation.