It’s now been over a year since I installed a Grant Aerona HP290 heat pump in my house to replace an Oil combi boiler, I’ve recently published a video update about the performance so far:
TLDR: it’s working well, house is warm and costs much less than oil 
System on HPM: https://heatpumpmonitor.org/system/view?id=748
I’m currently using EcoNext instead of EcoNet to interface with HomeAssistant.
Here’s the original installation video:
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