Elite marks operate on a window system?

I should probably be posting this in Reddit since the forums here seems to be only for people to whine but I was wondering if elite marks operate on a window system like in FFXI? I noticed a lot of Hunt LS would teleport to one place, get an A-rank mark as soon as pops, get the B-rank mark, and then move on to the next area. If nothing pops within 10 minutes or so, they just assume someone else got it already and move on. Its almost like they knew when these things were gonna pop and a B-rank always tend to pop shortly after an A-rank. This makes it seems like these things are respawning in the exact order and timing that the LS killed it last time. I think it would be incredibly stupid if these elite marks have a strict timer and are respawning after an exact amount of time has pass.

Most Bs pop more or less 1hr after dead. As for As they usually pop 3 hour and a half to 4 hours after dead. That what i have gather for my time hunting them. The S ones are poping 72hr after dead and some have pop conditions