[PROBLEM]
Starting "apt-mirror" and you've properly configured it and it was already working before, you might run into this error message:
apt-mirror: can't chdir to skel at /usr/bin/apt-mirror line 313.
[SOLUTION]
This simply means that it can't access the folder where the local mirror is located. In my case it was an external USB hard disk which was not mounted.
Mount it and try again.
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