Qavion:
You will get educated in due course when the A330s are in service with QF that on a Airbus you have a FMGC and MCDU, 744 Boeing speak is not applicable to this question (i.e. the FMC question on the 767).
Scallywag:
The answer to your question is in the Honeywell A320 FMS Pilots guide Pg 3.2-64. While this manual does not cover your question 100% the A330/A340 are similar (slightly different MCDUs).
During preflight the Thrust Reduction/Acceleration Altitude values are displayed in blue small text on 5L on the takeoff page with a default value of 1500 ft above the departure FIELD elevation.
They are modifiable by the pilots preflight, but not once the takeoff phase has achieved by the FMGC.
My suggestion for the difference is for a departure RUNWAY where an EO SID is in the database for that RUNWAY (ie not FIELD) that requires some special routing. To meet the single engine terrain clearance requirements.
For example the Jeppesen A320 Airport Analysis Manual for Mexico City (CFM 56-5A3 engine) has a range of thrust reduction values, and has a special procedure for the airport. Runways 05L/R require a 15 deg banked climbing turn at 5.0 DME MEX to 320 degrees intercepting and tracking on the 360 MEX VOR radial, 23L/R same turn requirements but at 5.4 DME MEX, direct MEX VOR, continue climb on the 360 MEX VOR radial.
RWY 05L Min Acceleration Height 800 ft
RWY 05L Max Acceleration Height 2445 ft
RWY 05R Min Acceleration Height 800 ft
RWY 05R Max Acceleration Height 2010 ft
RWY 23L Min Acceleration Height 1200 ft
RWY 23L Max Acceleration Height 2048 ft
RWY 23R Min Acceleration Height 1198 ft
RWY 23R Max Acceleration Height 2024 ft
I understand that the difference between these heights is due to the Obstruction limit weight requirements of FAR 121.189.
Cheers
Z