Warfare & Tactics

I'm trying to figure out how close a BM has to be to a plex or mission deadspace to count as 'in the deadspace' and pull you to the acceleration gate when you try to warp to it.

From my experiences of trying to warp to characters burning out of plexes from the inside, it seems like the deadspace extends at least a couple tens of thousands of kilometers into surrounding space, probably more than that if multiple rooms in a deadspace area are all part of the same deadspace area and not distinct 'islands'. Is there a point where a character mwding out of a plex will eventually leave the deadspace? Or does it expand dynamically?

I know this could also be in missions/exploration, but I figured all the FW people might have some experience with this with regards to in-plex PvP. Thanks in advance!