[Rules] Armor joining an in progress assault hex

[Pippers]

Your AFV may enter the hex with a 'Fire' activation and then see 12.3 'Optional Combat'. IF you so wish, the AFV can stir the hornets nest and the assault with all your troops can take place as per your Q.

Are you talking about the AFV assaulting on its own when you say "enter the hex with a 'Fire' activation"? Is there any reason you would want an AFV to assault on it's own, and then have the infantry assault on their own the next segment? The shifts that come with AFV with support infantry are nice.