Planner: Export your entire plan to Excel for powerful analysis, sharing, and more

I had a similar problem that required javascript to figure out, but I think I've done it using Excel commands instead.

I had exported and unhelpful columns which I turned into date format

I used =DATEVALUE(LEFT(I2,2) & "/" & MID(I2,4,3) & "/" & RIGHT(I2,2)) then =DATEVALUE(LEFT(J2,2) & "/" & MID(J2,4,3) & "/" & RIGHT(J2,2))

Where I2 was the start date and J2 the finish date, then extracting the text appropriately I shoe-horned it into the start2 and finish2 columns.

And it worked. Below is the graphic from my excel file and examples of the data columns below that. The colours in the excel graphic are just cells that highlight when matching the values in start2 or finish2 to create a very basic gantt.