Really old Campaign still showing as referrer

Hi,

Problem: someone is coming to my site repeatedly and it shows Google and a particular ad reference for every visit. Thing is, I retired that ad a while ago, there's no way this person is still clicking on that ad daily to come to my site. And yet every day it shows that campaign tag as the referral, via Google.

I understand Clicky does this weird thing where it attributes the original Google ad referral to every single visit that person makes thereafter, for about 60 days. Is that what I'm seeing here? There's no way this visitor is clicking that ad any more.