haven’t seen much chat on this - presume November? 
Probably November-ish. That said, I wouldn’t be surprised in the slightest if they change things up this cycle due to the goal of getting Nuendo/Cubase updates in sync - and perhaps even partially due to the delays in getting ARA2 up and running (even though it still open issues/missing features).
So…who knows? Most likely answer is mid to late fall, but it could be winter, could be an entirely new schedule.
Does anyone know what rumoured features or updates are speculated to be included ?
They keep that stuff under wraps. You don’t want competitors getting a look at what you’re working on to get an advantage.
There were some Feature Requests polls in the FR forum here. That might give you an idea as to what customers want to see, but don’t necessarily reflect what Steinberg is actually working on.
To be fair I’m completely happy with cubase 10.0.4. Anything else is a bonus from here on in.
Everyone has different wants/needs/desires. Cubase is a solid DAW, but I’d definitely like to see a few enhancements both big and small. No DAW is perfect though.
Of course, I’ve been there in the past being annoyed at things not being in place, but for my work flow I’m finally pretty pleased, which has taken a loooooonnng time to come with cubase.
Sorting out HiDpi scaling is something the most competitors already have sorted out, so Steinberg telling us it will be sorted on the next update would hardly be giving them any advantage; would it?