Pure and complete conjecture but.....
The new 20.83 is 13% heavier than the 18.13 and 18% lighter than the 25.4 All three of course the same diameter.
The formula for BC isn't entirely weight based but just setting up simple ratios and optimistically calling the BC of a .22/18.13 something around 0.04 and the BC of a .22/25.4 something like 0.055......id estimate the BC of this new .22/20.83 to be around 0.045-0.05.
If reality works out to a BC of 0.045-0.05 it'll be an amazing improvement over a .22/18.13. The .20/15.89 has a BC of about 0.048, so right in this window of what I am guessing the .22/20.83 will be, and is simply amazing for a 30fpe pellet. A few days ago I whacked a dove @ 170 yards with a .20/15.89 (again, BC very similar to what the new .22/20.83 SHOULD be). I'd been shooting golf ball sized dirt clods from 120-170yards before the Euro dove landed so I had rhe wind figured out pretty good. Anyway, just an example of how much better performance can be seen from a BC change as small as 0.01 (going from a 0.04 from a .22/18.13 to a potential 0.05ish from the new .22/20.83)
In short, these .22/20.83s have the potential to be MUCH better than .22/18.13, which has long been a favorite of many 30-35fpe pellet shooters. In addition, assuming s typical speed that pellets like or 900fps, you're looking at 37.5fpe so a bit more thump on target than the 18.13s too. Realistically, it's not going to be a new challenger for long range benchrest or Ultimate field target, but it'll dang sure be an improvement over the 18.13s for those hunters and happy-to-stick-with-modest-power pellet shooters amongst us.
And even shorter, I think this new .22/20.83 is gonna be GOOD stuff!