BOM Equation Incorrect Calculation?

So I've just come to purchase some stock but on the website the lengths are listed in feet.

Quick enough fix I thought  - add an equation column to my BOM.

But then I spotted it's not working.  Obviously I can work it out myself but this is a pretty dangerous issue.

Any idea what could be causing it?

My Length value is a config specific property and the BOM is sorted by it - I've tried using both the file property and the column in the equation - no difference.

SolidWorks you scored 4 / 8 and have just failed your Maths Exam.  Must Try Harder

On closing down the files and reopening SW managed to increase it's score to 5/8

but on shutting down and restarting we had a regression back to 4/8

SolidworksDrawings And Detailing