Axpert 5kVA 73.00 setting 04 NOr?

[Coulomb]

While updating a colleague's Axpert for capacitors and MOSFETs, I noted that it is running firmware 73.00. (I'm unable to read the firmware too, but that's another story). Setting 04 (Power Saving Mode) has a new option, NOr or possibly NOk. It still has the previous options of SdS (Saving mode Disable) and SEN (Saving mode ENable); NOr/NOk is the default option (or it would not have been noticed). It seems to draw slightly more quiescent current in this mode than in SdS, so it seems to be doing something different.

The owner is overseas at present, and the manual isn't in the box provided, so I can't check the manual to see what the new setting is about. Does anyone have a user manual later than 2.1 that has this setting mentioned? I'm curious about what it does. I'd also be interested in anything else that appears to be new in firmware version 73.00.