Screen painting broken up during notification and an AOD active (Fenix 7X Sapphire Solar)

I have a user reporting screen rendering being broken up during notifications when a watchface with an always on seconds display is enabled. This is happening on 

• Device Name: fenix 7X Sapphire Solar
• Firmware Version: 8.21

See pictures attached. Also note that the part of the watchface that is shown does not appear to correspond to the clip area which is drawn using the onPartialUpdate() call.

Also when he switches to a different watchface is switched to and then returned, he reports that the time is a few minutes off and the screen rendering is incomplete. (See the picture with the almost complete watchface shown.  The second hand is incompletely rendered and the time should be 5:15.  Also see part of the minute hand drawn in a different position.

As far as I can tell these problems don't happen on another watch model that I have here.

Is this Fenix 7X specific?  Does anyone know the cause or has seen anything like this?

Photo link:  https://c.gmx.com/@601543519135334994/62VLDDzzRwK-UwI56IxqiQ