I know when I came to replace mine, the replacement came with a kit of parts to fit many types of TRV base. I used eQ-3 bluetooth programmable heads which in 2019 cost me £15 each so not much difference to price of a mechanical head, and they auto worked out travel required, and had a report if travel too much or too little. The terrier i30 looks similar.
Since it would only work with one phone, when I needed to replace an Energenie TRV head, I used Kasa (TP-Link) as it uses a hub which can be accessed by multi-phones, again is came with a kit of parts to fit many TRV bases.
I can't see the point of fitting a replacement head which has * 1 2 3 4 5 6 as the settings when for very little more you can get one with is set with degrees C, and can be set to heat the room at selected times only. And is designed to fit on a variety of TRV bases.
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