Queerer things have proved true. Ursula has kept herself to herself with respect to alliances. Obviously she distanced herself from Gaude long since. There was a time I'd have speculated she and Yaxley were allied, but she plays her hand well. And she must have been clear of any damning link when Y fell.

Really, it's an interesting proposition. I did wonder about her reaction when Julius threw himself away against Lucius. I expected she might have demanded some satisfaction, but L indicated she wouldn't. Seemed certain of that. And so far as I'm aware she did nothing.

That doesn't prove L had something to hold over her, and it doesn't prove she's a traitor, but it also doesn't eliminate either possibility.