I just purchased the game recently on Steam, and have been completely baffled by this issue since I started playing. Whenever there is a battle with more than a couple of units, the deployment plans often get messed up once you click ready and move on to targeting. Units will exchange positions with each other, sometimes just one pair, and other times the whole army will start playing magical chairs. Needless to say, this is a huge problem when fighting a tactical battle where the outcome is highly dependent on the order in which units move and attack. Here is a screenshot of the last battle that convinced to put the game down for the day.

Deployment Phase

Targeting Phase

There is no trickery here. The only thing I did between the two screenshots was click on the ready button, and you can see my lead unit switched positions with its neighbor. Why is this happening? Are unit positions supposed to be randomized like this between deployment and targeting?