Instead of simply paying for aomei backupper, I created multiple batch files to back up my image directories and set up times for taskscheduler to run them at certain times on certain days.

Each directory that needed to be backed up got their own batch file. The contents of one was as follows (ignore the == part)

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echo n | copy /-y D:\backgrounds E:\backgrounds

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I have that set to run every three days around 1AM, to wake the computer to run the account, and to run whether my account is logged in or not. It's not the same as mirroring but I think it will be good enough for what I am trying to do.