Does the 'Pebble Ship' use a form of faster than light transit?

The pebble ship is definately not sublight speed. It left its destination of origin to arrive on a lifeless planet elsewhere. Instead it is faster than light but doesn't seem to use propulsion or any type of sublight engine or engineering. This is precisely depicted in the scene with the shadow and the pebble craft, although it might be hard to wrap your head around shadows move faster than light itself. Google the question is a shadow faster than light? In principle, shadows can move faster than the speed of light. ... If the shadow is large enough, it could move across the surface faster than light. This is an illusion that darkness travels faster than the speed of light, and it is still agreed that no physical object can travel faster — since darkness has no mass. The pebble ship uses Faster Than Dark Transit!!!!

In short, we don't know. The ship very briefly appears at the start of Prometheus. It demonstrates that it has anti-gravity capability (by hanging in mid-air) but we don't see it in transit, nor is it described in any detail in the Japanese-language novelisation or the original script where it's just referred to as

"a vast black SHIP [that] hangs in the sky."

We do know from the Prometheus commentary that the writers originally envisioned that the seeding ship would be an identical replica of the 'Derelict' seen in Alien, which we know to be an FTL ship. Having replaced it with a different design, I can't see any good reason why they'd also make it a sublight vessel, one which would take hundreds of years to reach its destination.