I've heard a couple rumours on this one from a reliable source so I figured I would share. First off, as you probably know the design reveal had been pushed back due to Covid, but from what i've heard the 2 sides of the development centre, CSES and the CMLC are at odds again. Apparently one side of the equation wants to incorporate 'social distancing measures' into the permanent and final design of the structure. It's unclear which side but if I had to guess it's the CMLC. I'm not exactly sure to what social distancing measures they want to incorporate but obviously it's not the brightest idea since Covid is not permanent.
Second off, apparently the exterior design is going to be very similar to the new BMO centre expansion, same looking gold/copper exterior cladding, similar to the T-Mobile Arena in Las Vegas. This isn't necessarily a shock since the 2 buildings are supposed to work hand in hand with each other. I have no word on the Interior design yet.
Thirdly, for all you Saddledome lovers out there, apparently the city and CSEC are looking for ways to incorporate the Saddledome into the future of the Rivers District rather than tearing it down. They believe the building has some historical significance to the city and they'd like to keep it around for hosting events, although i'm not sure what events because the building is essentially useless for anything other than sports. I doubt they find a feasible way to keep the building intact since the upkeep for the Saddledome costs a fortune. I honestly can't see it not being torn down.
Fourth off, the arena is likely to feature an exterior office building for staff members, Likely to be around 6 stories or so in height, rather then having the offices inside of the Event Centre similarly to what the Saddledome has now. However that is all I've heard in regards to this.