Looking at what you have, the folder which is by name dated needs to be removed daily to remove today yesterdays folder and data?
I have an easy solution for this but I want to confirm some information before sharing the batch script with you as for I don't want to destroy data on you that may be at the destination that goes through a daily purge in prep for new data.
*** Is there any data that needs to remain at
C:\warning\excel\stream or can this folder named Stream and all data in the root of Stream and its subfolders be wiped clean of all data and repopulated with the latest data?
Basically the batch I have in mind uses a RD Foldername /S/Q which will remove Stream and all data files and folders and subfolders and then create a new folder named Stream, and then copy the latest CSV file to C:\warning\excel\stream
But holding off on sharing it in this response because it can be bad if you plan on any other data remaining at Stream.