PWentworthBucknell,
That is not a solution for all scenarios, we have a special scenario in which we enabled our photostream on one mac, and uploaded photos with it as far back as October 12th, 2013. That mac has since moved on, and now we have a new mac; this new mac when you view PhotoStream will only reach as far back as October 21, 2013 even though we have older photos, thus we are stuck with those photos until they expire.
We have the all the boxes checked for iPhoto > Preferences > Photo Stream, which includes the upload and store the last 30 days of your photos on iCloud and download them to all of your devices, as well as the Automatic Import setting.
One would think this would actually download the last 30 days of our Photo Stream, instead it clearly says on the header of iPhoto: My Photo Stream (October 21, 2013 - Nov 8, 2013). Our Apple TVs still show the photos in Photo Stream past October 21 (from the last 30 days). We would like to delete some photos pertaining to expired events, but simply can't get the to appear in iPhoto.
Got more ideas? I'm stuck.