Sorting a Dynamic List of Data

Hi,

I have data in the attached file arranged as follows:

"Source Data" sheet
Data in columns A to L will be updated daily by pasting from another workbook. On any given day the data in columns A to L may have more or fewer rows than the day before.

"Lookup Table" sheet
The aim is to return the data from the "Source Data" sheet; the selection depends on the Data Validation choice in cell O1.

I would like to be able to sort this dynamic list of data - ideally by clicking a single button - in descending order of the values in column L.

Can someone please suggest a solution?

Thanks!