In case you've forgotten, I inline what they think the volume trends look like. I'm doubtful their prediction will come true. Why would I think that, other than to be curmudgeonly? I'm not expressing any great faith in the CMIP5 models, which predict something later. No, it's more of a feeling that volume doesn't respond linearly, especially when the ice gets thin (see-also their figure 8, though that's for May; it's a shame they don't show it for September too). I could be wrong, of course. Sadly 12-15 years is too far away for any kind of useful bet.
* Dosbat also sees the light, from 2015.