The opportune shut down of the HEPI Pump during the vent allowed the HEPI Mechanical to respond to the change of state.  The Z & Y dofs trend 10s of um with the Y sliding 60um.  X waffled around in a window of 3um so basically didn't move.  The yaw and tilts are a couple to 15urads so again maybe nothing.  See the attached trends remembering the local sensors these are derived from are from the top of the SEI Piers to the suspended HEPI.  So, there is most likely coherent motions relative to the floor that these don't see.