Copying Jon Peck's response to the same question posted to SPSSX-L (for the benefit of readers who are not subscribed to that list).
Jon Peck wrote
The current fix pack brings the system up to 28.0.1.1, so if that is what you see in Help > About, you are up to date.
--
Bruce Weaver
bweaver@lakeheadu.ca
http://sites.google.com/a/lakeheadu.ca/bweaver/"When all else fails, RTFM."
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