The squeezer took H1 out of observing at around 19:02 UTC, because the SHG PZT ran out of range.  The attached screen shot shows the PZT hitting it's rail, this is made using the ndscope called "Locking signals" linked from the SQZ overview screen.

The squeezer guardian tried to recover from this on it's own, but when it re-opened the beam diverter, no 3MHz signal showed up on the OMC DCPDs.  I cleared the history of the sqz ASC loops, after which everything locked up fine.  

I've made a function called turn_off_sqz in the squeezer manager guardian, which is called in several places where there was previously boilerplate code. I've added to this function to clear the history of the ASC loops after turning off the squeezer, this is loaded and will hopefully allow the squeezer to relock itself more smoothly in the future.