On the Google sign in page - where you can choose which identity you want to sign in as if you have more than one, my old photos still appear.
I have altered on my profile and in Google+ but the sign in page still persists in showing my old ones.
Maybe it’s just the image cache. You can clear the browser’s cache. Or try Ctrl+F5 or Command+F5 if you are on a Mac, when you are on that page.