Actually had to update my “Shelly Plug S” once I added it (and in the cloud) today (5th dec 2021) - but still could not get past the “Select icon” - screen in Homey. So the problem is not just in Shelly 1L.
I now have three new “Shelly Plug S” for the X-mas lighting that I bought to include in Homey flows… but stuck at this point.
Turned out that I had an old version of the Shelly-app which showed wanting an update after a restart of my control-unit. After that - it flagged that the units needed further update (which it did not do before).
So, finally - with new firmware - just as you pointed out - it worked!