You might be splitting hairs here. No doubt the present day Turks/Israelies are the current "possessors" of the land they squat, but that in and of itself doesn't make them the owners per se. Ownership should imply one of two things. One, that they homesteaded an abandoned piece of land, or two they acquired the land via contract (non-coerced, non-violent).

So while it is necessary from time to time to defend ones property from invaders, the act of doing so is not prima facie evidence that you're the legitimate owner. I could go to Times Square and set up a bunker in the middle of the street, arm it to the teeth, and hold everybody at bay for weeks. However, even for that brief period of time while I was holding out, it is certain I'm not the owner of said land I occupied.

Ownership and expropriation (or even occupier and possessor) are different concepts. An auditable paper trail or chain of custody, may illuminate the situation for the Cypriots. It could reveal the true owners. Reuniting property with owner might be a bit tricky though.