I've added both 32 and 64-bit SEP packages, version 11.0.6005.562, to a group of Clients in SEPM, and set the upgrade window to 2-6 AM over 3 days. It has been the full 3 days now, and about 80% of the computers report having the new client.
However, a few servers still note having client version 11.0.5002.333. Upon further inspection, opening C:\Program Files\Symantec\Symantec Endpoint Protection\Download on some of these servers reveals that they received a file called "PKGb6388acd7a9fcafe517ffac8165a2a44
11.0.5002.3331", last modified at 5:59AM during a day in the upgrade window. Could SEPM be pushing the wrong version to these clients? Or is there another problem that needs fixing to get SEPM to properly update these clients?