I did that, wanted to put it back to 0.5. But it was refused, kept to 0.1 because of the added +/- buttons.
There’s also this PR: Range of Plugwise thermostat is [0-100] instead of e.g. [0-40] degrees celsius · Issue #104023 · home-assistant/core · GitHub
I will create a PR that puts a max of 35 on the upper limit.