For this model, we offer an option to transfer the chips containing programming from the old screen panel to the new screen panel. Normally, these pair the original screen to the logic board; if there is a mismatch, it can cause a slight difference in how the mini-LEDs react, which are built into the lid.
On 14" A2442 and A2779 models, we transfer the chips across by default, since we believe the screen is unusable if this is not done (purple bars along the top of the screen).
On 16" A2485 and A2780 models, the screen performs fine if not calibrated, but the mini-LEDs will not all evenly light up when the brightness is being increased/decreased across the midway point. This happens even if swapping one screen assembly to another on these models, and the only option to resolve it is by calibrating a new display assembly through Apple (meaning it has to be purchased new from Apple, very expensive) or transferring the chips across from the old screen panel, which is what we do, if requested.
Please see below a video showing an example of an uncalibrated A2485/A2780 screen panel, noting how the screen appears brighter around the notch area when adjusted around the halfway point (although the LEDs which are brighter can vary).
Since this is minor, and something we haven't seen other repairers talk about online, we offer this as an additional optional service, since it is not necessarily required. If you wanted us to do this, you can select this from the dropdown on the repair page. If not selecting this option, it is recommended to turn off the auto brightness feature, so the brightness is fixed and doesn't regularly adjust over the halfway point, which can be jarring.