Quite the contrary. The transmission in an Aqua is not belt-type CVT, but rather a planetary gear system (in fact, 2 planetary gear systems). Not like normal CVTs and conventional transmissions. It does not heat up as high as conventional transmissions, and Toyota doesn't mention any change interval on the transmission oil, maintaining that it is there for the life time. Also, in the Aqua, the transmission oil pipes don't pass through coolant to cool it off, rather it is air-cooled, if you can call it that. The transmission oil pump stops pumping when the car is moving on battery power only, and only pumps when the engine is running. This design would not have worked had it's transmission been running hotter than conventional transmissions. It is, in fact, at a lesser temperature in the start, and moves to about the same or the lower end of the temperatures maintained by conventional CVT and AT transmissions (around 80-85 degrees C).
Keeping in view the above stuff, I believe that it is not necessary to change the transmission oil so early. One should keep inspecting it, and if a need is felt, get it changed after about a 150k kms or so.