In a forecast, open the supply chart to see required replenishments. If you want to see replenishments which are required because of open transactions instead of just forecast demand, disable 'Apply forecast' to remove forecast demand. This will show the open stock movements based on the expected dates  entered in the transactions. If your open transactions booked in deplete your stock, you'll see AIM calculates the required replenishments. You can toggle these controls to check your forecast expectations versus what is currently booked in.