According to someone who is supposed to know more than I do about this, this is called a "splash" and is very common in plumeria. She stated that Slaughter Pink is well known to display these color shifts. She said that plumeria color genes are unstable and this causes "splash" like this to occur. often when there is some stress, such as very hot, humid climate. She said I could see this even without stress conditions. She further stated that unless I see viral changes in the leaves and particularly see that the plant is in decline, it is not virused.
I am attempting to understand this and have contacted the PSA. Unfortunately, that site doesn't seem to have a way to submit photos. Hopefully, someone with expert knowledge will contact me via email and I can send him/her the photo for evaluation.
