I never let bird poop stay on my car I always wash it off the same day.
I hear what you say re the water based paint, but I'd be interested to hear from those in the know here, if the lacquer is water based too, if it isn't why should bird poop burn through that?
I think you are going to have an hard time getting Renault to move too far on this issue if all the car is affected, take a look at the date when I put the first posted this thread then add on a month.
I've been a pain in the a$$e to the local dealer,
, and another dealer not too far out of my local area.
I've heard it said before that poop can affect water based paints, surely if this is true the car is "protected" with something thats not fit for that purpose. Bird's, and bird poop aren't really all that uncommon, now are they?