How to notify the difference between Local time and RTC time of timedatectl

Issue

How to notify the difference between Local time and RTC time in timedatectl

As https://access.redhat.com/solutions/5017611 says, In RHEL8, timedatectl can not be used to check 11 minutes mode is on and working or not.
Command timedatectl reports "System clock synchronized: yes" even if "rtcsync" is commented in /etc/chrony.conf.

In this situation, As one of workarounds,we can check if 11 minutes mode is working by monitoring Local time and RTC time

# timedatectl
               Local time: Tue 2020-01-21 15:45:55 JST
           Universal time: Tue 2020-01-21 06:45:55 UTC
                 RTC time: Tue 2020-01-21 06:45:54
                Time zone: Asia/Tokyo (JST, +0900)
System clock synchronized: yes       
              NTP service: active
          RTC in local TZ: no

Do we have a tool to monitor Local time and RTC time?