When time came to go beyond 5.19.13 I found the RAID TW stopping in emergency shell unable to find the / filesystem on RAID. The key rdsosreport.txt message Andrei B pointed out was: "dracut-pre-trigger[373]: rd.md=0: removing MD RAID activation". After 6 unhelpful rebuilds of 6.0.12 with various modifications in /etc/dracut.conf.d/ I learned that use of rd.hostonly=0 must be coupled with rd.auto or rd.auto=1 to avoid halting in the emergency shell.