I wouldn't hold it past January. And currently the market is underpricing this combo, while maybe tomorrow it won't.
Gotta say: I love discovering things like this, because they give me hope for what I can learn in the future. From my current perspective, managing such an animal would be damn near impossible (delta, sure - but if I have to manage the other greeks, how the ever-loving hell would I do it without screwing up everything else?) And then some pro comes along and goes "what's the problem? We do crap like this three times a day, and twice that on Sunday. No big deal." OK, phew. Means it's humanly possible.