Thanks for the advice. I only wish I could use it.
The website has a complex architecture and after a few yrs, I still haven't got my head around it. However in a nutshell it's only after the 200 response is sent, do we know it's an expired event.
Therefore we can't send a 301 or 410 response code. I am trying to re-use some event urls but itís a long tedious process.
Also these pages have 1000's of links including .edu links.
In some instances the parent category is also expired. When this is the case I gather that the Canonical Tag will work and the "value" is passed up. At least we should be able to centralise the value of these pages.
However this could be a false positive as once we create new events within that category the content will be different and the Canonical Tag will be ignored.
I'm running out of options on this one. Changing the site architecture is not an option as itíll cost at least 6 figures.