I believe you may be reading it wrong. I'm seeing improvements ranging from -8 dB to -10 dB in tinnitus loudness, which is pretty damn good. There is a return to baseline it seems but I would not mind using the device every day for 30 minutes if it means having less bothersome tinnitus.
Here is the replay of the presentation that Thomas linked above:
https://wsw.com/webcast/jeff174/freq/1851714
David Lucchino said they feel confident on their single dose methods. I'm cautiously optimistic for their next trials.