During SARS many airlines permitted free reissues, so there is some precedent. The current level of conflict has been going on in Sri Lanka for decades, and there were no free reissues even when the airport was attacked and several airplanes were destroyed a few years ago. So there are precedents both ways. If the route is no longer operated, it is an involuntary reroute and for dated sectors you have a choice of CX paying for you to fly a different airline (e.g. SQ), or of changing the routing. For open-dated sectors it becomes a free re-issue (you don't have the choice of forcing travel to the ticketed destination).