It seems very old school automatic to me...
Assuming there is an update, would this be something that would come over the WiFi connection the car has to my home internet?
In previous instances, since this is largely customer preference, it's filed as a TSB, and, if an owner requests it to be addressed, it will be addressed by a service center. So, no, I do not expect it to be downloadable via an OTA update. If enough people complain, maybe?
Under very light throttle the cvt changes ratios fairly fast. The hesitation being discussed becomes very apparent on steep inclines because it becomes a near stall and a lurch before the cvt drops back to a lower ratio.
Unlike traditional automatics where the torque converter or torque converters release then have some give during gear changes the cvt locks up and stays locked up. This hesitation is much like shifting to 2nd gear in a manual transmission car at a low rpm while giving very little throttle and lugging or nearly stalling the car. The simple fix is more throttle or the cvt catching the mistake and dropping back to a lower gear. Which the cvt will do before stalling the car but I have had the car stumble in cases where this has happened. Especially steep boat ramps when I left the car in AT mode vs dropping to manual 1st gear etc.
Alas, it is similar to some performance automatics, such as the TH-350 and TH-400 with overdrive performance "tuned" Chevy transmissions. It feels very similar too, like the transmission is in limbo as it drops past one or two gears down into a lower one... eg: 4th->2nd or 4th->1st, with the same pause and then hard yank when it engaged the lower gear.
The torque converters in those old school vehicles do absolutely nothing whatsoever. They're just a housing with fluid and fan vanes (turbine and impeller vanes). Nothing smart, nothing special and never connected on both sides. The differences to that design were in the "lock-up" torque converters that also had a clutch assembly built into them, so that motive force was actually physically locked to the transmission.
Our CVTs seem to very accurately simulate an old school performance automatic, including the odd shift hangs that would happen in the old school automatics when the vacuum advance module wouldn't dump vacuum pressure quick enough if you suddenly let off the accelerator.
All of you can duplicate that little oddity by flooring your Ascent, wait for it to "downshift" and grab, and then entirely let up on the gas pedal. Try it a few times. A number of times, the car will sit at high rpm, as if it's stuck in a "gear". Various old school vacuum controlled automatics did the same thing. How interestingly odd. Anyway, there's an update that purportedly will make it to the Ascents to "fix" that odd "shift hang", for those who care.