Just from exposure to the air, in 4 weeks. Two components, cut from the same piece of mahogany, went from A (lying flat in front) to B (standing on edge). (Behind is a 3rd piece of a different wood, ignore)
I live on the ocean in Southern California, and we’ve had, by our standards, a wide variety of weather so far this year. Maybe that’s accelerated the process, or does this seem normal to you?
Cherry will react to sunlight in much the same way. So much so that you have to be careful how you stack the pieces that you are working on. One day is enough to leave a significant color difference. I’ve messed up and ended up having to take a few swipes with the plane to “erase” my mistake.
We hung cherry kitchen cabinets. The windows cast a shadow across the top of them, so the bottom 2/3 deepened in color much more than the top, thus producing a shadow across the faces of the installed cabinets. The funny thing is that I didn’t notice it for a long time. Since it was produced by a natural shadow, it is exactly what the eye expects as “correct” shadowing and the eye is used to that shadow being there. So, at night, when the lights are on, it’s just the cabinets you are accustomed to seeing, shadow and all. One day I realized, “Hey, there cannot be a shadow there with the light on” and that was when I realized what I was seeing (or not seeing, really).