I finally had some sun today for about 3+ hours. I've taken the 2 sets of keycaps out of the jar containers and have some results and possible cautions to report.
Both sets of keycaps are white (off white) Kinesis Contour keycaps with 8 medium-blue home row keycaps. Set 1 is decal, set 2 is doubleshots.
There are some keycaps that appear new original, and there are keycaps that still have very little yellow. It's 90% or better.
Keycap set 1-(10x solution 1 day, 16x solution 3 days) started a medium yellow. It lightened the 8 dark keycaps slightly.
Keycap set 2-(16x solution 3 days) started a very heavy yellow. It lightened the 8 dark keycaps significantly. Now they are powder blue.
Both sets of keycaps, even though started out very, very different shades, appear the same now.
Initially I was surprised and disappointed to see the 8 home row keycaps significantly lighter, but once I put them on, I like them considerably better, they're not old-school industrial retro-blue anymore. Plus, they are the doubleshots, which I think are overrated, but I'm keeping anyhow. So fortunately, no downside. But that is a BIG caution if you are dealing with some reto-thing you might be restoring...having the color leach out or get bleached could possibly ruin your day.
I don't think the OxyClean was very powerful when I dumped it out after 3 days. My hands aren't dried out like when I mixed it. I'm thinking the best choice is to use a stronger solution in bright light for a shorter period of time, rather than let them sit for days on end. My solution was just OxyClean and water. I didn't use hydrogen peroxide (instead of water) which I think is what makes the solution very toxic and super-strong.
I will wait until our local foggy season is over before I do anything else. No sense fighting the fog for days. I'm planning on popping all the keys in solution again for half a day+ in full sun for a final, yellow-B-gone, 95%+ or better finish. I'll also wait to do the glycerin and xanthan gum paste at that time as well.
I'll post a couple pics tomorrow of some comparison results.