We have experienced some problems with pipe styles after installing SP2. If we choose a style to not show pipes (data referenced) in plan, save and close the dwg and then reopen, the styles are changed to the original style. This problem occured on two different computers with SP2 installed and at least two different files.
Civil 3D is referencing the style of that part from the part list when it syncs. A possible workaround would be to build a copy your current part list or edit the default styles in the consumption drawings part list to the desired _No Display style.
From the Sp2 readme:
Synchronizing a Pipe Network with a part swapped in the source drawing now changes updates the style as expected.
Sounds like the fix noted in the readme is changing the style in the consuption drawing on sync vs the part swapped in the consuption style.
Matthew Anderson, PE Product Manager ICP Autodesk, Inc.