[mirror-admin] MirrorManager doesn't realize a site is out of date?

[Columbia University Mirror Admins]

A user of my mirror reported a problem to me trying to retrieve an  
EPEL package and when I went investigating I discovered my mirror  
appears to be quite out of date with upstream:

http://mirror.cc.columbia.edu/pub/linux/epel/5/x86_64/?C=M;O=D

vs.

http://download.fedora.redhat.com/pub/epel/5/x86_64/?C=M;O=D

While I'm trying to get this resolved, I also decided to check  
MirrorManager to see what it thought of my mirror and was surprised to  
find it thinks the site is up to date:

https://admin.fedoraproject.org/mirrormanager/host_category/1836

Can anyone explain why MM would think this?

Thanks,
Dave Coulthart
Columbia University Mirror Admin

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