Quest - DS - Wallaby - Quest and VG failure

Today was quite an interesting day. It started when I thought the weaklink broke on tow. I was low and had almost 10 minutes of flying between 100 and 150 m off the ground. But I couldn't really get the thermal and had to land. On the ground I found out that the weaklink hadn't broken, but the release was open. It might have touched the base bar and released. I'll check whether that is possible.
So, I had to get in line again and relaunch a little later. The plan was to do Quest - Dean Stills - Wallaby - Quest. And I set up a comp route in the Compeo with an extra turnpoint (off route, huge radius) to test the optimized route feature. I got a really nice flight, which had a scare when I wanted to start final glide. The VG suddenly released, see the bolt below:

The bolt has no locking mechanism at all, so you might want to check yours before you launch next time ;-)
The release was sudden and I was weightless for a split second while I felt a big bang in the glider. I thought something went wrong with my primary hang strap or with the hang point. I thought I had so much bar pressure because I was now hanging on the backup strap which must have slid backwards on the keel. Not a nice feeling and quite an adrenaline rush. I took me some time to realize that it was just the VG... This is how it looked like:

So, the rest of the flight, I had to take it really easy, there was no point in pulling in the bar. I completed the flight and was happy about the little triangle. Here's the tracklog. We could have done more today, but tomorrow seems to be the big day. I'm curious...