Although there are some significant changes to the stages, the migration phase is still happening simultaneously and you have a specific reserve step. You move units first, and the process looks pretty much the same as before, with advance, regular moves, or retreats. Monsters and vehicles have to move around units of the same type, and it looks like you measure the hull against ungrounded flying units. The previous move still adds d6 to the movement rule, and you can’t attack or shoot (unless there’s a special rule).
The retreat step remains the same as before, no attacks or shots are allowed, and you cannot move back into range. However, you can retreat against your opponent’s patterns (like when you’re surrounded but want to get out of combat). Now, if you roll 1 or 2, a pattern will die, so you have to go back to do it! A great example is the Space Marines that are surrounded and want to get out.
When you do a desperate escape roll, the entire model will be destroyed, regardless of the wound! You can move freely on most pipes, barrels and other objects. However, to climb something higher, you must use movement. You can also move through walls, but not through them. Flying units move diagonally over the terrain (path in the air). Keep in mind that this path is not a straight line, so it can make some measurements a bit uncomfortable, but not too complicated.
Although flying units can move past other units as if they didn’t exist, however, in most cases their path will end at a greater distance than traveling” On the ground”.