Deep strike and Combat squads

[Tynskel]

Well, if this one's doing the rounds again, this is what clarifies it for me; SM faq

Q. If I have two or more special characters that exchange
the rule Combat Tactics for another one, when must I
decide which to use? Does it have to be on the army list or
can I decide before each game? (p51)
A. Decide before each game starts. You will need to let
your opponent know once the mission and deployment
type have been decided but before any units have been
deployed.

Even GW think that deployment is done in the deployment phase.

Agreed, but their FAQ for Combat Squads contradicts this.