Well the market seems to think this is a loss for BKL. CH has...

Well the market seems to think this is a loss for BKL. CH has been at the helm for 9 years - how many CEOs stay in place for 9 years? She has overseen dramatic growth, OS expansion and supply chain reengineering. Its probably a good time to move on for her and the company. This allows a reset for everyone. Current company status is new baseline for new CEO rather than 9 years ago.
As for Aust Post I wouldn't be surprised if it goes through some (more) massive changes moving forward. CH's retail / supply chain knowledge is likely on point. Also, far-fetched but why not a privatisation. Amazon is set to drive a lot more retail dollar through the post box. Lots of opportunities and by no means a boring gig. I reckon this is a good thing. Hoping the market thinks so too in due course.