Before we started the fine tune of the balance for ISI Testing, I locked up the HEPI.  There appears to be a real rotation of the HEPI as measured by the Dial Indicators compared to the signed off position of Wednesday 7-25.  I locked down corner 1 (NE Pier) and then locked up Corner 4 (SE).  When doing this, one watches the dial indicators keeping the Indicators reading the recorded position.  When I went to corner 3 (SW), I noticed a big offset.  I was suspicious of the cable pulling activity had disturbed this DI.  So I released all the stops again and I see a coherent shift in the indicator readings.  This suggest to me that it wasn't any DI bump but something real. If so the move is on order of 0.5mm ==> likely about 2x requirement in rotation.  I was rushed a bit hoping to get the ISI ready for weekend testing so I just locked the HEPI.
When testing is complete I want to do a more careful job of unlocking HEPI and make sure nothing is pulling it out of position.  If it still looks real, I may request another IAS look to confirm or correct what I see.