For a prosmetic and probably all automatics, how much the gas paddle is pressed tells the ecu (electronic control unit) of the car how aggressively you want to drive the car.
If you just press the peddle very slightly it will accellerate and change gears as if you are driving a manual with a relaxed and laid back manner, that is not accelerating too fast and just changing gear on the earliest possible moment considering the performance position of the engine.
My civic prosmetic changes gear at this stage when the rmp is just between 2.5k and 3k and if i am on a strait road it generally tries to keep the rmp between 2k and 2.5k
This is the most fuel efficient
My civic has no problem in this scenario as many would think that i am killing the engine as the engine has enough torque to move the car with ease, it goes to around 80km/h and i am still getting a 2k rpm and i effectively use this in Islamabad in my commute. and its not harm in getting to the next level when needed
If you press the pedal hard the ecu detects that you are driving the car more aggressively and thus it changes the gear in a more aggressive manner and that is it takes longer to change gears and lets the engine rev up more than before. In this situation my civic prosmetic changes gear after reving up to about 3.5k to 4k and tries to keep the rpm at around 3k to 3.5k
This gives good acceleration but consumes more fuel
if you really go hard and press the pedal to the floor the ecu in a civic prosmetic go to the most aggressive setting and red lining the rmp before every change that is going even beyond 5.5k before changing and tries to keep the rmp as high as possible
this is the most effective for very high acceleration as it uses all the power range of the engine, but its the most fuel hungry
When ever you move from one setting to the lower (by pressing the pedal down further into that range) the ecu shifts down from the current gear. If you are moving in the first and most laid back stage and you press the pedal to the floor the ecu shifts down two gear at once.
And you dont need to lift the foot to change the gear, you just need to adjust it so the ecu does not think that you want to go harder on acceleration. But yes sometimes just letting some pressure off the pedal will make the ecu engage the top gear if its not engaged yet. sometimes my civic even engages the overdrive and goes below 2k when in the first scenario
I hope it helps