Hi,
After a couple of months without any issues using 2.4.48, we suddenly encountered a crash again, but this time on 2.4.48. It was the exact same symptom, and the same assert failing as in my original message. It appears that the issue happens a lot more rarely in 2.4.48 compared to 2.4.47, so ITS#8841 possibly had an effect on my issue, but did not solve it completely.
I have a core dump I can run tests against, if you need.