[Vimes]

That could indeed offer a solution...?

I think so. E.g. when TV is turned off, this wrong variable is set to false. Therfore, when TV is turned on again, this value blocks reconnecting cec. I compared an old and a new log. I guess 'm_bActiveSource' should indicate that a cec source is active/connected, while new introduced 'm_bActiveSourceSent' should indicate that an 'active message' was sent. Due to using m_bActiveSource instead of m_bActiveSourceSent, this causes strange behavior.

You can also compare setters and getters:
SetActiveSourceSent => m_bActiveSource = setto;
ActiveSourceSent => return m_bActiveSourceSent;
This confirms that accidentally a wrong/similar named variable was used.

opdenkamp doesn't seem to have been active for a while though..?

It seems that he is inactive since Apr 7. But maybe one of the kodi devs has contact...

I do not like to ask but if anyone here has the ability to push this in the appropriate direction it would be most appreciated

I had confirmed the issue for me at build #315 and then noted those findings on the git, after help was provided by Milhouse who made a special test build to confirm that by reverting those commits it would resolve the issue.