On the custom Kanban Boards, when the user completes the task assigned to them, they can "signal" downstream that the kanban card is ready to move by setting the card to Ready to Move.
It appears the user must MANUALLY remove the Ready to Move indication after moving the card to a new column, rather than the move action automatically triggering the removal of the Ready to Move indication.
@Kelley Cooper - thanks for the question! Unfortunately I don't believe there is a way to automatically remove that label after being moved to another column on the custom Kanban Board. The person who pulls over the object would then need to "un-mark" the ready to move state.
I do think this is a great addition for the custom Kanban Board and would recommend adding an idea to automate this to the Jira Align ideation board. Here's the link (you just need to sign up and then enter your idea): https://ideas.jiraalign.com