Any inspire 4 ETA rumors?

Are there any rumors on when (or if) there will be an Inspire 4?

I'd seen thoughts it would come out in October. My Inspire 2 is in its decline. I can't wear a device on my wrist at work, so the Inspire on a clip is my only option.

I don't want to get an Inspire 3 if I can baby my current along until the Inspire 4 arrives, but if it's never coming, I want to get the Inspire 3.

Thanks!