I imagine a bowling ball rolling down a blanket stretched tight at half light speed. The bowl shape of the blanket in front of the bowling ball would be very different from the rear. I'm just pointing out that if gravity goes light speed, then something coming toward the earth at half light speed will have a longer delay for us to feel the gravity, and as the object leaves the earth, its gravity will linger longer. Maybe it's true, it boggles my mind.
If gravity is light speed, then an object travelling toward you at light speed will have no gravity until it has touched you. We should be able to detect shock waves like a jet breaking the sound barrier breaking all the windows in a community because the sound builds up. Gravity would build up too.