Final update: kernel 7.0.0-31 has been promoted to resolute-updates and reached our production pool. Confirming on a production 8 vCPU guest (Xeon Gold, XCP-ng 8.3 UEFI): sched_clock correction is now -0.17s, down from -143s when this thread started. The ttyS0 removal stays in our cloud-init templates as a general optimization; the underlying regression is fixed.