In SRW, whenever you move while flying , your energy will drop. Which means when you move 1 space = -1 nrg. Say Unit A has 130 of 140 EN. It can move 11 spaces. You select the full 11 spaces to move. At the end of that movement, the game would deduct the 11 EN for it's move. If you waited until the movement was over and then cancelled it, it' will deduct 11 EN and then add 11 EN. The bug occurs when you cancel though. If you wait until Unit A has moved 10 of the 11 spaces you sent it to move and then cancel it, you get 10 EN. So you'd be at 140/140 EN. If you sent it 11 spaces and stopped it at 5 spaces, you'd get back 5 EN.