Attached is the 18 hours trend of the X arm WFS from last night.  Seems like it's doing something sensible. Happy periods are indicated by pink arrows at the bottom left.

• Before the WFSs were engaged it was quite aweful despite people manually aligning it. This is partly due to the tidal feedback going to the ETM top mass (we'd be better off going to HEPI).
• Then WFS was engaged, the arm was happy for about 4 hours.
• Sheila started Arnaud's measurement before she left, which made injections to both ETM and ITM.
• After the measurement was done, the arm came back on its own and enjoyed its happy life for another four hours.
• Then the arm locked itself to a higher order mode, which lasted for about four hours, then something shook ITMX for an hour or so, and after it's gone the arm relocked to 00 mode again.