I am not sure what triggers it, but when I am working on large raw photos (22MB) occasionally (maybe 3-4 times) when I reopen Lightroom to the same catalog, the spot removal that I applied are now scattered randomly around the photos.
(1) Some photos have 30-50 spot removal uses and some may have half or a 3rd.
(2) this problem only affects the photos that I have used the spot removal tool on in that specific directory (it does not affect the entire catalog).
(3) all my other adjustments are not affected at all.
(4) [this is odd]. Every virtual copy has the same identical scatter pattern.