You may take into account the units selected for
deployment by players with a
turn order before yourself. For example, if you are the second player in
turn order, you are only permitted to get information about the
first player's selected units, not the third or fourth.
Deployment stacks themselves are created simultaneously and privately. You can use your hand to obstruct while making your
deployment stack, so your opponents may know what units you have selected, but not the order in which you are deploying them or which units have been grouped. Only once all players have locked in their
deployment stack is the stack
revealed. The top
unit is open information, and some information about grouping will be evident from looking at the stack, but you are not permitted to look through each other's stacks and see the order of your opponents' units.