I really don't see this as being that big an issue. I can always see the spot the police are supposed to be at before I get there. Yes it disappears once you get to the zero spot, you are passing him at that moment and no longer have an opportunity to slow down or move over, it's too late by that point. So mark your thanks before you get to him and you are fine.
When I have a police warning pop up, I wait until I get within half a mile or so and then start looking for him. As soon as I see him I mark thanks. (I still feel the 2000 yards is too far out as often by the time I get to where I could even begin to see him I've been distracted by that annoyance called other vehicles on my road/in my way
and forget to look for him).