Unlike the others though the 3-4 different waves of spawns all drop within seconds of each other instead of waiting for the deaths of the others first, they don't go away when you die, and the timer is the shortest of any of the spawns. I've gone through this 4-5 different times now and I really think the spawn timer is screwed up.
As in. The first three drop, then 3-5 second later the next three spawn, 3-5 seconds later the next three, and another 3-5 seconds later the last three. So little to no pause inbetween and the timer on these guys is less then the reconstruct timer. I know this because I had these guys spawn on me, kill me and my team quickly, due to having another purple frag on me another person on the team loaded rez and came back for me. We went through another cycle of the team getting killed trying to get to me, came up with another plan, and just as they were getting ready to come after me again... the spawns vanished. I had a good minute or two left on my reconstruct timer.