CDN cache can indeed take days to update. For example, Academia design was launched April 23 in 2014, and a report on outdated icons was made on April 27thApril 27th. The issue went away on its own, and I expect this one to do as well.
replaced http://meta.stackexchange.com/ with https://meta.stackexchange.com/
replaced http://meta.academia.stackexchange.com/ with https://academia.meta.stackexchange.com/