Usually thrust reduction altitude is reached first, then acceleration altitude and I've never seen it done the other way around, so I don't know what the real aircraft would do.
Noise abatement procedure 1: at 800ft AGL reduce to CLB thrust, climb at V2+20 with takeoff config up to 3000ft AGL. Enter 800/3000 in the MCDU.
Noise abatement procedure 2: at 800ft AGL reduce climb angle to accelerate, when reaching flap retraction speed: thrust CLB, flaps retract, then climb at speed for best climb angle and at 3000ft accelerate to normal climb speed. I would enter 800/3000 in the MCDU but keep the LVR CLB flashing with takeoff thrust until I start retracting flaps.
In both of these the acceleration height would be 3000ft, well above the 800ft or roughly 1000ft-ish for the thrust reduction altitude NADP-1 or -2 respectively.
Here's what AI say, which may be false 
But anyway, if I switch the values, it works as expected:
1500/2000: "LVR CLB" shows up at 1500 ft.
2000/1500: "LVR CLB" also shows up at 1500 ft. 
So currently it just seems to pick the lower value, got it.
Yes but AI does did read the flight crew operating manual and did not program it, nor has it ever flown the A320 (and probably never will). I haven't flown the real thing either but I know more than a text generating AI that is supposed to sound convincing, even if it's hallucinating.
nor has it [AI] ever flown the A320 (and probably never will).
I hope so!
At the acceleration height the FMS switches to the climb phase, which then causes the LVR CLB display to flash if you haven't yet decreased the thrust.
It works different then compared to Boeing aircrafts (within Aerofly),
where the thrust will not be reduced until the TRA is reached,
even when its being set above the accel height.
PS:
Regulations such as FCOM and FCTM should actually be more meaningful than the AI.
Another solar flare perhaps
