Wang's transformation conjecture for Dwork's p-adic hypergeometric function

For $a\in\mathbb{Z}_p$, let $l\in\{0,\ldots,p-1\}$ be the unique integer such that $a+l\equiv0\pmod p$. Let $\mathscr{F}^{\rm Dw}_{a,\ldots,a}(t)$ be Dwork's $p$-adic hypergeometric function, viewed in

$$\mathbb{Z}_p\langle t,t^{-1},h_{a,\ldots,a}(t)^{-1}\rangle.$$

The involution $\iota$ sends $f(t)$ to $f(t^{-1})$.

Wang's transformation conjecture. If $p$ is an odd prime, then

$$\mathscr{F}^{\rm Dw}_{a,\ldots,a}(t)=((-1)^{d+1}t)^l\mathscr{F}^{\rm Dw}_{a,\ldots,a}(t^{-1}).$$

If $p=2$, the same identity holds up to sign.

This conjecture proposes a transformation formula relating Dwork's $p$-adic hypergeometric function at $t$ and $t^{-1}$, analogous to classical hypergeometric transformation formulas. The cited work of Wang formulates the conjecture, while its resolution is not established in the supplied source.