Using the HL-8548 wtih 5.5.25 version of the firmware (and 5.5.23) it is observed the GSM serving cell and neighboring cell report may be swapped in the AT Command Sheet.
The reason, I see multiple “serving cells” for GSM and only one “neighboring cell”
I know there were some changes for KCELL in 5.5.25, but it did not seem to change anything here.
Also many of the values for RSSI GSM and TimingAdvance GSM appear out of range.
When in GSM only I also see some invalid tower types being reported for UMTS. Values of 105 and 237 come up every now and then. These we ignore as there are no UMTS towers at this point (all values are also 0).