I think to build this, you should consider having a field called "Item", another field called "Modified date" and another field called "Status"... This would be a temporary table that you load to make your final product...
If you aren't needing the historical data in the model, then you can do this:
Max([Modified date]) as [Modified date]
Group by Item;
That way you will only have the latest status for each item
But if you are wanting to keep the historical data in the model, then you don't need the bold section.
So this is what you'll need to do:
Load your order table (the date field is called OrderDate)
Load your Item Status table (All Dates must be in one field called Date, All Status in 1 field called Status)
(These 2 tables need to associate on the field Item)
Create a straight table with the Dimensions:
=IF(Date=Date(AGGR(Max(IF(Date<=OrderDate,Date)), Item, OrderDate),'DD/MM/YYYY'),Date) //Make sure this calculated dimension is suppressed when null
You can hide the calculated dimension (or any other dims) on the presentation tab of the chart properties.