Unfortunately PR83 has been discontinued. How long a given manufacturer will be able to offer a paint with the original formulation will depend on how much of this pigment they have in reserves. On a different note regarding lightfastness, of one of the ingredients in this blend is Prussian Blue. In general with Prussian Blue, we advise doing one's own lightfastness tests in different white paints to see how this pigment may behave. Some preliminary research may indicate that the lightfastness of PB27 could be affected by the use of various mixing whites. One resource on this topic is a video from Rublev/Natural Pigments which shows their tests from their own variety of Prussian Blue (PB27) in various mixing whites. In this case the combination with white created different lightfastness ratings: https://www.youtube.com/live/xFn74zdaDHc?feature=share&t=1286.