I think Steve is correct in his guess that the HL versions of the beloved EODIS3 have become weaker in the dark area.
Here is the result (luminance only) of a small test with an Xrite Display Pro Plus (06/2020; 2000 nits) and the Calibrite Display Pro HL (06/2023; 3000 nits).
Contact measurement with both sensors placed close to each other at the same time in the center of an LG C2 TV.
Parallel measurement with ColourSpace version 1691 on 2 PCs with identical settings (intelligent integration from 1 nit, AIO and frequency mode almost identical result). Measurement times almost the same.
Pattern legal 10Bit 422 from PGenerator 1.5.
This was certainly not a scientific test, but it shows me that the new Calibrite HL sensors have probably not been improved in the dark area.
However, it is pleasant that the Rev. C firmware is compatible with the Rev.B in terms of control.
Peter