One temp sensor and 3 TRVs giving wrong offset on first TRV

[arthurdent2095]

Running 3 TRVZBs and one thermostat (netatmo thermostat with value via a helper )

One of the 3, the first one in the set, seems to be registering 1 degree warmer than the other two. Which might be correct but would think the offset is counteracting this over time but isn't. The other two are aligned. There is evidence that BT is indeed setting the offsets over time as all 3 offsets are getting edited. The offsets haven't maxed out or run out of limit.

Is this normal I was thinking not.

BT 1.5.1
HA Core 2024.5.1

Let me know how to grab debug will happily try to see what's going on.