rbphdmi option doesn't work on RPI-3B after OSMC update to Kodi 19.1

[old-fogey]

The output of the log when run in debug mode suggests this new issue is somethign to do with the response from bin.tvservice. Worked perfectly before recent update from kodi 18, but not sure what the bin.tvservice response was at that time. Debug/log output as shown:

2021-08-12 13:45:52.802694: [rbphdmi] HDMI Power off delay: 300 seconds (ignored when CanSuspend is yes)
2021-08-12 13:45:52.803244: [rbphdmi] Player OnStop delay : 5 seconds (ignored when CanSuspend is yes)
2021-08-12 13:45:52.803630: [rbphdmi] Path to tvservice : /opt/vc/bin/tvservice
2021-08-12 13:45:52.804017: [rbphdmi] Path to vcgencmd : /opt/vc/bin/vcgencmd
2021-08-12 13:45:52.804395: [rbphdmi] Path to ceccontrol : None
2021-08-12 13:45:52.804826: [rbphdmi] Ignore Active Player: No
2021-08-12 13:45:52.805239: [rbphdmi] Ignore Library Scan : No
2021-08-12 13:45:52.806547: [rbphdmi] Connecting to Kodi on localhost...
2021-08-12 13:45:52.811259: [rbphdmi] Connected to Kodi
2021-08-12 13:45:52.811804: [rbphdmi] HDMI power management thread - initialising Kodi and HDMI state
2021-08-12 13:45:52.899748: [rbphdmi] HDMI is [on], Screensaver is [active], Player is [inactive], Library scan [inactive], CanSuspend [no], CanDisable [yes]
2021-08-12 13:45:52.900430: [rbphdmi] HDMI power off in 300 seconds unless cancelled
2021-08-12 13:50:52.901778:Thread-1 : bin.tvservice (checking if TV is powered on) calling subprocess [/opt/vc/bin/tvservice --status]
2021-08-12 13:50:52.923127:Thread-1 : bin.tvservice response: [state 0x120009 [HDMI CEA (16) RGB lim 16:9], 1920x1080 @ 60.00Hz, progressive]
2021-08-12 13:50:52.925283: [rbphdmi] Display device is not turned on, no need to disable HDMI