Vanguard Combat Drones

I’m having some troubles with this modules. It says that when shields are <50%, they heal either hull or shields.

 

How do they repair the hull? I’ve never seen them repair hulls. When your shields go below 50%, they start healing the shields not matter how low your hull is. When your shields go above 50% again, they stop repairing.

 

So do they actually repair the hull at some point or is it just an error in the tooltip?

only shields lol