Less power "normally" means that the point of impact will be lower than with a higher power level.
BUT, as I was shooting one of my springer pistols yesterday, I was shooting on the lower lever (of two). Then I tried the higher power level, the pellets point of impact "dropped", it didn't go up as I had thought that it would..! I shot both low and high power several times, all...with the same outcome (same pellet).
But as I said, "normally", if sighted in at one power level, lowering the power level will lower the pellets point of impact.
Because I shoot 25 yards or less, there's no reason for my guns to be shooting at 900fps. So I lowered the power of "all" of my adjustable guns (including my .22, Maverick Compact) in the last week or so. In only one gun was the point of impact much lower. One gun was "slightly" lower, and the rest, had no point of impact change at all. You have to figure out what your gun is doing.
Shoot targets on paper, this way you'll know exactly what's happening to the pellets point of impact.
Mike