Spartan Games has posted the stats for the recently released Defence Platforms for Firestorm Armada. The platforms are available in the Planetary Defence Group boxes for each of the core 6 factions, which also include a battle station (the stats for those are in the respective faction’s fleet manual).
It seems that the Defence Platform stats are separate because the platforms are intended for use in scenarios, not general battles. You can grab a copy of the PDF from the Downloads section on the Spartan website. Click “Firestorm Armada” and it’ll be under “Model Statistics”.