How frequently your Canon EOS R5 has locked up?

Here is an update to my prior post  (https://www.dpreview.com/forums/thread/4621975#forum-post-65888276)

I was out photographing eagles again today for 2-3 hours. After some time, I began to realize that the freezes seemed happen when using Animal eye focus back button auto focus, IS on the lens being turned ON and writing to the CFExpress card, not the SD card.

I used the same Canon R5/ RF 100-500/ RF 1.4 extender set up that I described in my post above. I stared with two fresh LP-E6NH batteries in the grip and took some 2800 images. The first 2200 images were on a 128GB Delkin Black CF Express card which I low-level formatted before leaving home. I used this card in Alaska earlier this year for thousands of images with no issues. (Also with the R5 with FW 1.40 and an adapted EF 100-400 II lens)

I had 10-12 freezes. The image in the viewfinder froze and the LCD went grey. This time, instead of turning the camera off then on, I tried holding down the shutter release. If I held it down for ten seconds or so, the camera made sort of a clunk that I felt as much as heard, then the LCD blacked out momentarily, and the camera started working again.

I never got a freeze when I was using the Large Zone AF: Horizontal autofocusing zone (which I use for birds in flight against a clear sky). When I was at shutter speeds over 1/2000 second I usually turn the lens IS off. I don’t remember getting a freeze with the IS off. Finally when my CFExpress card was full and the camera switched to the SDHC card, I don’t remember getting any freezes there (590 images). I tried experimenting to confirm these observations, but I ran out of card space.

By the way I never had a freeze with the R6 (firmware 1.50) under the same conditions (IS on, Animal eye focus, etc.) over some 1600 images.

p.s. I’m not sure what I am going to do with this information, but perhaps someone can find it interesting.