personally i would wait
starts to loose its antifreeze properties and anti corrosion properties . . . . do i need to say what both of those can do to the engine lol
So it is definatly done in the service?
depends where you take it to be honest. Ask if its done, if its not ask them to do it
I didn't think it was part of the service TBH
right type? coolants coolant even the best tell you that
do the lot yourself and do everything!