Cypher & Co

[TB0N3]

With the recent dataslate for Cypher, I have been looking for a way to use the model in question. I have a converted DA+BA Fallen Angels Army... But I'm not completely sure if my ideas are rules-legal

Idea 1 (this is the simplest one):
Primary Detachment: Blood Angels DeathCo
Formation: Cypher (solo)

Idea 2 (hummmm)
Primary Detachment: The Tyrant's Legion
Formation: Cypher (+The Fallen Champions)

Idea 3 (it's a little more complex)
Primary Detachment: Imperial Guard
Allies: Blood Angels DeathCo
Formation: Cypher (+The Fallen Champions)

Are those legal? Or does the "Come the Apocalypse" rule take precedence in the third case?

Thanx in advance!!!

[gwensdad]

Isn't Cypher by himself just an HQ selection and he's only the Formation when he's with CSM armies?