This is something I'm interested in too.
I don't think any of us here would moan at strapping this to our head for 30 minutes a day for the rest of our lives for relief from tinnitus anyway, but I wonder if either of these are realistic:
1. Like with medication/antibiotics, you start off on a high dose (using the device every day) for 6-12 weeks. Once the tinnitus calms down, you go onto a lower maintenance 'dose' and maybe use it twice/three times a week just to keep everything ticking over.
2. If the fusiform cells can become permanently hyperactive, and for the sake of this point we'll assume that's because they receive less input from hair cells dying, then should the opposite also be presumably true? The device after several months of use may permanently calm these cells down and, once you reach near-silence, you can stop using the device? If further damage occurred to your ears and the tinnitus rears its head again, you'd just repeat your treatment cycle.
Susan Shore's team may not even know the answers and the day 1 adopters may be involved in follow-up studies to determine the above, maybe not of so much interest for private use as once you own the device, you own it. But maybe for people that are undergoing chemotherapy that can induce tinnitus? Hospitals may have some of these devices on hand that people can check in/check out during their treatment to keep tinnitus away.
This along with the frequencies being user changeable are at the top of my 'I'd love to know' list.