I wonder if this is a fallout of the recent Carillion collapse that made the investors "nervous" (aka soiled pants)? Never mind the actual crappy nature of capita and their actual state of real or "flexibly managed" accounts, they've been sailing regardless, patted on their backs by consecutive UK governments. If they crash, we'll have another round of indignation from our Glorious Leader(s), no less.
I guess a sure sign of real trouble at capita would be, if it hasn't happened yet, when the flock at the very top of Capita quietly take to the skies, greener pastures, retirement, personal and family reasons, pursuing new options, etc. etc.
but then, it takes more than two to domino...