Auto update heart rate zones not working

Hi - starting from, I think, watchOS 9 Apple will set your heart rate zones based on resting and max heart rates observed during workouts and saved in Apple Health: View Heart Rate Zones on Apple Watch – Apple Support (UK)

…only it doesn’t work, or rather it doesn’t keep the zones automatically updated based on recent data.

Under Watch app | Workout | Heart Rate - it says “Max and resting heart rate values are updated on the first of every month” but I’ve had max heart rate readings higher than the initial max set several times recently. My running app (Tempo) picked up the new max, it’s disappointing that apparently Apple can’t do it. It didn’t update 1st of October either. Note that you can set it manually. I had assumed that meant you would just need to input the new resting and/or max values and Apple would helpfully recalculate the zones based on that but no - you’re expected instead to set all the zones yourself manually - that seems peculiar and almost punitive! Is this auto-update of resting and max heart rates working for anyone please?