LWT doesnt seem to tally with WD Curve

Hello,
Query regarding Daikin pump and LWT…

I am monitoring my Daikin EDLA04E2V3 ASHP, integrated into Home Assistant (HA) 2025.2.4 with Onecta integration 4.1.14.

I have set a WD Curve as attached, the setup runs from this with no thermostat influence, so just from the curve VS ambient, and all seems to be reported well, system works, and LWT is matched to the curve for ambient temps since I started about 2 months ago whence ambient has ranged from -2 to 5C. Today we have a “huge” 10C and the LWT is stuck at 35C. According to the curve it should be around 31. I then dialled in an offset via the MMI that would normally - and has - affected the LWT. I put in +1C, then half hour later another +1, then half hour later another +1. The LWT is still stuck at 35C.

I know the offset works because at night time my HA automation applies a -7C offset to bring LWT down and cool the house for sleeping. I know the pump works because there are no adverse diagnostic reports and this morning it was around 4C and LWT was about 39C. It then began to “warm up” outisde.

This is wierd. Is it the case that the pump will not operate below 35C, is there something happening with low LWT of 31C which is what the curve should be driving?
TIA.