@jmoneygrip so after having an issue with wrist hr reading locking to a high bpm when slowly walking, I read and took on board a few suggestions by forum users and it has made the difference.
1: I did a 12second reset (just in case after the firmware update)
2: probably the suggestion that’s made the difference: I really tightened up the watch whilst doing a gentle walk and had good, expected and consistent wrist hr readings.
I have a feeling the slighter cooler weather did reduce my readable hr flow through the wrist or shrank the wrist slight so that the watch wasn’t making that solid connection, fingers crossed.
I use a chest strap for anything other than a gentle walk so its a minor thing anyway but its always nice to know you have the accuracy on the wrist when you need it.
Thanks fellow forum users and mods for the thoughts and suggestions around wrist hr accuracy.