chrisN,
From another glider pilot, also an ex-professional though not as a pilot,
Yes, there was an overspeed condition that caused a warning an disconnection of the A/P. However, that overspeed condition was very brief and not really a problem. Shortly after that the airplane encountered a vertical gust that increased the AoA to alpha-prot and put the FCS in high-AoA protection mode which caused the zoom climb.