Drawing on the answer of "B_26_Gaurav Joshi"

If you agree naming of your incoming files as YYYYMMDD you can find the latest by NAME rather than by Last Modified. The name often indicates the most recently updated in a batch of files that may have arrived in a random order.

Then use the same technique as "B_26_Gaurav Joshi" outlines but with file name segments rather than modified dates to sort for the latest data point.

BUT - there is a problem both with this solution and the overall idea of a sort. Every day the folder gets bigger and the sort is slower. I am seeing > 15 minutes for 4000+ files.

The further solution is to archive some files (ha obviously) or if you want them all on hand use a modified date filter in the Get Metadata so you are only looking at receipts for the last few days and progress only those into the sort. Effectively using both techniques together for the optimum result :/