Somfy blinds "preset" via Alexa

Hi all,

I’m working on getting HA and Alexa to play nicely with my Somfy blinds. I have this 99% working thanks to the excellent guide here Amazon Alexa Smart Home Skill - Home Assistant

I can open and close the blinds via HA and via Alexa.

The final piece of the puzzle is getting the blinds to go to the “preset” position via Alexa. The “lovelace” dashboard has a handy gadget that allows me to set the blinds all the way up/down or set them to “my position”. This works great.

Alexa, on the other hand, allows me to select the options “open”, “close”, “preset”. The third option would seem to be the obvious winner here, but it appears to do nothing.

Any clues as to what the mismatch might be or how to debug it?