The chances are probably somewhere between infinitesimal and "forget it", despite the salivation of some over this prospect.
From the Kurdish point of view, there simply isn't enough widespread support for separatism. More freedom, certainly (and rightly so), but not outright independence. Even with regards to regional autonomy, it already exists to a certain degree with regional councils that report to national political parties (the KCK was supposed to be this until it was co-opted by the PKK, which is why it's being shut down). More importantly, even in the provinces where separatism is ostensibly highest (which isn't too close to Mt. Agri, just to be clear

), there are still major divisions among the population, usually along tribal or clan lines. If these regions were to hypothetically separate, the likely result would be a tribal bloodbath.
From the Turkish population and government point of view, any redrawing of the borders are also impossible, since any government that allows this would be toppled swiftly, and not by the army. The Turkish public has seen too many casualties over the last 28 years to accept anything less than the total eradication of the PKK, regardless of how long the conflict continues.
More importantly, the balance of the conflict is better tipped in favour of the Turkish military than it was in, say, the early 1990s. The kinds of casualties that we see now a couple times a month were almost daily occurrences back then (I'm speaking from my own memories of living in Ankara between 1989 and 1991 and watching TV), with nowhere near the kinds of casualties being inflicted on the PKK at the same time. The re-organization and re-equipping of the Turkish military has made a very big difference, from UAVs to more attack helicopters and the widespread use of mine-resistant armoured vehicles. It's not much of a surprise that the PKK has begun targeting the police instead of the army or Jandarma, since the police are much softer targets (literally and figuratively). The targeting of police is also deliberate in another way: it weakens the Turkish government's ability to keep the PKK out of the cities, which is where they are more likely to build support - the poor villager or farmer sees both the PKK and the military as a nuisance that keeps him poor, but the PKK is glorified among some of the Kurdish urban poor, who often take the state's handouts for granted but seem to consider it 'fashionable' to riot over the stupidest things. One might also argue that since the police are now the representatives of the state more than the military (thanks to the AKP's gutting of the military), the PKK is also symbolically attacking the AKP, but that's a stretch, IMO.