Fenix 6 Pro / Suddenly Not working Properly

Hi,

Went out walking today and my watch started to buzz/vibrate but no incoming call. It then began to cycle through various screens whilst I watched with more intermittent buzzing and vibrating occurring. At one point it said I had no HR and I thought I might be about to have a bad day. When things settled I was unable to make selections with menu buttons, took a long time to get itself back to watch face. When I push any button there is a loooong delay before anything happens. 

After reading forums I tried to do a reset but now there is just an animation on my watch screen of different coloured boxes radiating from the centre outwards. Before that a screen with black and white detail came up which had ESN number / SKU Info Missing / 006-j1149-23 Rev0E 

Pushing back button is now taking me through a lot of 'test' screens for various functions until I get a screen that says 'Press and hold power key to disable forced test mode'

Has this new update bricked our watches? I've only had mine since January and before that owned  an Instinct and Vivo with no issues. I have not done any sport with it and only wear it to work or out walking.  To say I am disappointed is an understatement. If I take it back to get a replacement will I just get another bricked 6 pro in the end with the same problem?