The z-Parity Alexander polynomial span conjecture for virtual knots

Let $K$ be a virtual knot. Let $n$ be the minimum number of real (non-virtual) crossings in any diagram of $K$, and let $z^{e_{\max}}$ and $z^{e_{\min}}$ be, respectively, the highest and lowest powers of $z$ appearing in the z-Parity Alexander Polynomial of $K$.

z-Parity Alexander polynomial span conjecture. The exponents satisfy

$$e_{\max}-e_{\min}\leq n.$$

The authors state that they verified this conjecture computationally for virtual knots with fewer than $6$ real crossings. Its general status is not established in the supplied text.