Yes because the file name never changes as we are still in the same day. It will only create a new filename tomorrow as the date in ymd format is the unique part of the file name. If you want every file to be unique even if there are multiple file uploads on one day change the simpletime nodes to output the full date including also the time and change the property in the template nodes to use that instead or in addition to the ymd. This way you would have a file for every upload.
Edit
Here is the flow with the time added to the name so every time you upload it will be unique and no file be overwritten in the dropbox.
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