In Sonic the Hedgehog 4: Episode II the player can cancel the move by pressing the Tag Action while flying, and doing this will make Sonic jump from Tails' hands. The player can also attack enemies by flying underneath the enemy.
In Multiplayer mode, like Submarine Combo, Tails' movement is controlled by Tails' player. If Sonic's player presses the Jump button, he will jump off Tails' hands, and both players can either can cancel the move by pressing the Tag Action button or let Sonic simply drop from Tails' hands.
Using the Copter Combo Tag Action, or any other Tag Action as Super Sonic will revert Sonic back to his normal state.