Plugin automation not working

I noticed something very strange today.  It seems plugin automation is no longer working correctly.
 
Steps > 1: Create a project that has some plugin automation in it , 2: Save project, 3: Close Sonar, 4: Open Sonar, 5: Open project
 
Now when playing the project, none of the pluigin automation is working.  The automation envelopes are displayed but are inaccesible through the automation lanes.  The plugin -> parameter targets are also non-existent in the edit filter dropdown. nb. applies to both VST 2 & 3.
However the Pro-Channel plugins are available for selection as automation targets.
 
I've also tested in 2016.10 & 2016.09 upd2 & the problem also exists there. I don't recall this being a problem in these versions, so I'm wondering whether the problem was introduced with the installation of 2016.11.
 
Is anyone else experiencing this?

It's happening with all plugins as far as I can tell.  I've tried with plugins from multiple manufactures that are normally very well behaved.

A few common ones tried so far:
Cytomic - The drop
Melda - MBandPass
IzoTope - Trash 2, Vinyl
BlueCar - Gain (stereo)
AAS - Ultra Analog Session 2
 
Also, noticed that if the project is saved with the automation lanes visible, then on opening the automation track is displayed & plugin is displayed as a option in the edit filter dropdown BUT the only entry in the sub-menu is 'Unnamed'! ...hope this provides some kind of clue to the bakers?

Good question & I should've mentioned this at the start! - Yes, read automation is active.
 
Automation playback works without problems when it has been created in the session.  It doesn't work when it has been loaded from a previous session.

@karhide: Thanks, it'd be nice to know if anyone else can recreate this issue.  Although I'd be surprised if you could, given that other plugins work for you.  No plugin I've tried has worked!