From the 'Detachments and Formations' Draft
FAQ:
Q: When listing Formations, sometimes it states ‘1 model’ (like 1 Tomb Spyder), while other times it lists ‘1 Unit of models’ (like 1 unit of Tomb Blades). Are these interchangeable?
A: No. The former means a single model of the type listed, while the later means a single unit of the type listed.
So does it say '1 Stormfang Gunship' or '1 unit of Stormfang Gunships'?