Command points have priority over everything. In your
turn, spend them however, wherever, and whenever you
want with no restrictions, interrupting another Space
Marine’s actions if desired. In the Genestealer's turn, you
have to wait until one of your Space Marines sees a
Genestealer do something. Then decide if you want to
spend any command points – you may do so to carry out
a single action with a single Space Marine anywhere on
the board (not just one that saw the Genestealer do
something). After spending any command points, check
for overwatch shots for Space Marines that didn’t have
command points spent upon them.
