When you open the page Item Availabilty by Event from a Sales order line (through the factbox) the view presented is limited by the date in the sales order line. This is in my opinion a (usability) bug, because the sales rep cannot see the possible supply which might be in the system after the current delivery date from the sales line. So he/she cannot look for the first possible delivery date. And the Item Availabilty by Event page has no possibility to change this date filter, which is really annoying. The sales rep has to go back to the sales line to change the delivery date further in future and then again open the Avaliability by Event to see if that date does the trick. If not he/she has to do it again.....Or they have to go to the Item Card first and open teh availability from there...

So it is better to show all transactions which exist in the system with maybe a marker to show the current requested delivery date from the sales line. Or just make a filter available which the user can change to see if supply is available later....