Weibel's vanishing and regularity conjecture for negative K-theory

Let $X$ be a Noetherian scheme of dimension $d$. For a contravariant functor $F$ on schemes, call $X$ $F$-regular if, for every $r\geq 0$, the map $F(X)\to F(X\times\mathbb{A}^r)$ is an isomorphism. Weibel's conjecture.

$$K_m(X)=0\quad\text{for }m<-d,$$

and $X$ is $K_{-d}$-regular. This predicts vanishing of algebraic $K$-theory below the negative of the dimension together with regularity in the boundary degree. It is proved for schemes essentially of finite type over a field of characteristic zero, but remains open in characteristic $p>0$ except for curves and surfaces.