Firmware corruption - how to reinstall core firmware - hard reset fails to help

Last night about 7:15pm, my 6x Sapphire appeared to be working normal.  At least it was showing the time on  the watchface that I had been using since the release of the 6x.

By the time I reach home after a two hour drive, something had gone wrong.  

-My first observation was that the watch face was on one of the stock watch faces.

-Second observation was that the time was not accurate

-Third observation was the BT connectivity with the watch was not working.


I spent the next couple hour trying soft resets, hard, resets.   Removing the watch from the Garmin Connect mobile and re-adding the watch.  I even wiped cache/data on the android phone and reinstall GC mobile.   Nothing but nothing would get solid BT connectivity.  All I can characterize this was, the BT connectivity partially worked.  During "new device" setup the phone and watch would notice each other, but without fail during the initial sync, BT connectivity would be lost and remain lost.

During this time, I started to suspect something faulted in the watch. I was hoping (and I am still hoping) that somehow the firmware got corrupted somehow.  Though I had no activities, not was the watch actively doing anything on that drive home.   I attempted a factory reset from the menu in the watch, selected yes to remove all settings and data.  And it didnt work.  After the restart the history of my activities was still there.  However, the watch was not acting very odd.  locking up.  Trying to enter into the watch menus was failing.  button navigation seemed to work, but nothing was being displayed.

At this point, if its not something seriously corrupted, then the watch just has some type unusual to my years of having Garmins, type of hardware fault.

Before sending the watch back to have it checked out, or replaced for a different unit.  I thought I would try to re-install some of the firmware.  so I have two questions.

1// anyone else have anything equally unusual with their 6x before?  did you fix it somehow?

2// I am guessing I could use the procedure to install beta firmware, but instead of actually installing beta, I could install the last known/good firmware.  Would that work?
I am still looking, but have not yet found, a post that describe how to basically re-install everything from scratch. with a good/clean software firmware package.

Thanks in advance for any help and suggestions