I have added some examples for this specific task here:
How do I transfer new/modified files only?

comfortablynumb wrote:

I need to create a scheduled task that will upload files only for the current day. I looked at the synchronize option but that won't work as I don't control the destination directory.

Why that means you cannot use synchronize?

I could use synchronize if there was a way to have WinSCP only look at files created or modified on the day the task runs, and I have to schedule this task to run multiple times per day, then email the results.

If you want to upload files with modification date in a certain day, you need to generate the script on the fly with the certain date.
There are many examples on how to generate timestamp into script, e.g. here:
Downloading file to timestamped-filename

Hello,
I need to create a scheduled task that will upload files only for the current day. I looked at the synchronize option but that won't work as I don't control the destination directory.

I could use synchronize if there was a way to have WinSCP only look at files created or modified on the day the task runs, and I have to schedule this task to run multiple times per day, then email the results.

Can anyone help?

Thank you!