Not sure I'd be so pessimistic about this. With legs < 30min this would actually make sense - *if* there is any payload left.
However, as is often sadly the case, they manage to make the maximum buzz with minimum hard info. A lot of speculation floats around. Does anyone know any actual numbers except for the motor specifications (weight / power are known)?
In particular:
* what capacity battery?
* how many kW charging?
* what mass for the battery is actually true? 1000kg has been floated, but no source given as far as I can see. However 1000kg would mean MTOW minus empty weight = zero for the DHC2, even when taking into account that the electric engine is lighter than the combustion one by at least 350 pounds. So that can't be the full story... Did they increase MTOW for this? Otherwise for more than ~1000 lbs battery weight 6 persons on board should be be impossible.
* Battery swapping? This has been floated around, too, but would seem really weird for a floatplane... It also seems kind of useless, since for a leg of 20mins with 30min reserve from the last landing still left in the battery out of the 60 mins total endurance, you'd only have to charge from 50% to ~85%. This can be done with relatively high speed charging, so to get below 15 minutes for those 35% should not be a problem. Probably more than current minimum dock turnaround times, but not that much more to warrant a complicated swap operation...
Anyways, doing this with a 1947 design Beaver of all airframes, is so weird and wonderful that ol'Havilland in his grave probably has a big fat smile on his face...