Perhaps the reason for Tim Churcher resigning at the same time...

Perhaps the reason for Tim Churcher resigning at the same time is that he expected to be offered the CEO position and wasn't and instead the position is being out housed, that could explain the reason he is leaving.

With the CEO to simply step down is strange, I don't think that getting close to retirement stage is good enough reason, people in power like to stay in power, they don't just step down.