For rubberband:
My experience in working with U-2s was circa 2004 - 2005. Don't know when your operating experience was. The frequency of us losing the mission, or elements of it (due to one of a variety of subsystems going wrong), was high enough to get out of the noise level.
No further comment, as
1) any data I had on that was turned over to my relief when I left that job and
2) actual metrics on that system still covered by an NDA, and NOT for publication.
Given how precious the assets were to our mission, we sometimes felt the loss of a mission more keenly than other times. When they work, you get some great products out of them.
Cheers.