I want to show that for a connected covering $p:E\to X$, if $\phi\in \text{Aut}(E,p)$ is a covering automorphism, then for every evenly covered open set $V\subseteq X$ s.t. $p^{-1}(V)=\bigsqcup_{\alpha}U_\alpha$ we have that $\phi$ permutes the open sets $U_\alpha$. I know it permutes the points in the fibers, and I know that $p(\phi(U_\alpha))=V$ but what if $V$ is not connected? I'm thinking about the fact that a part of $U_\alpha$ can be mapped in some $U_\beta$ and another one in some $U_\gamma$. Why can't this happen?
I managed to prove it in the case $X$ is locally connected: in that case I can always find connected evenly covered neighborhoods for points in $X$. So if $V$ is connected and $p^{-1}(V)=\bigsqcup_{\alpha}U_\alpha$, then $\phi(U_\alpha)\subseteq U_\beta$ for some $\beta\neq \alpha$ (since the action of $\text{Aut}(E,p)$ is properly discontinous) and then we cannot have $\phi(U_\alpha)\neq U_\beta$ since $p(\phi(U_\alpha))=V$ and $p$ is injective if restricted to $U_\beta$.