Label non-current event pages

[mattstratton]

Being on the sponsoring end and not the organizing end, I've noticed a recurring problem from our marketing team members - they use google search, hit the events page sponsors tab, and pull old prices, or sponsorship availability. This has burned them/me a couple times by them thinking an old event is already sold out, or, using older pricing in the budget. As I'm sure most might be aware Google continues to return the old events for some time after publishing newer events (eg, search chicago devopsdays...I get the 2022 link first, the 2023 link 2nd or 3rd).
So with that in mind, does anyone else see a potential usability (confusion) issue that needs to be addressed? Taking the old pages down would be an option, but then we have a "loss" of valuable history (its still in git, but keeping it published has some historical value IMO).

Idea here is that we will have the pages that are NOT the most current year have some kind of banner across the top to identify as such, ideally with a link to the current iteration for the city.

[mattstratton]

so the biggest challenge here that I see is what is the simplest way (computationally) for determining "what is the most recent version of a city?"

I guess you could spin through all the city data files and match and make sure that whatever one you are currently in is the "end" of the list for that pattern match, but this seems very expensive (since it would run a LOT; basically on every page)