We have recently found a problem in several assembled boards which failed ICT.  We found several vias which had become opens after
assembly.  We had the open vias sectioned, I sent Steve Z. some pictures to post on his site.  I would like to have your opinions on what may
have been the cause for this failure.  So far it seems to have occured only on boards having two date codes from our board vendor.

Thanks for the support.

Keith Calhoun