The server level 3.1.2.30 introduced an error in expiration processing such
that the wrong policy attribute may be used to expire data.
 To encounter this situation, the following would need to occur:

1) A given file would need to have multiple inactive versions of a file.
2) The file has no active versions (the file was deleted from the client
filesystem and an incremental backup was run).
3) When expiration is run, all versions of the file are eligible to be
expired under the "RETAIN EXTRA" policy attribute.

In this error, the last version of a backup file may be managed by the
 RETAIN EXTRA policy attribute instead of the "RETAIN ONLY" policy attribute.

This can only occur if:

multiple inactive versions of the file exist when expiration is run.
all the inactive versions are eligible to be expired under the RETAIN EXTRA
when expiration is run.

In this situation, the last backup version of the file can be deleted incorrect
using the "RETAIN EXTRA" policy attribute when it should have been
 managed by the "RETAIN ONLY" value.  The description above describes
how this can occur.

IF YOU HAVE ALREADY APPLIED 3.1.2.30 and you are exposed

1) Halt the server
2) Set the server option EXPINTERVAL 0 (in the server options file).
3) Re-Start the server

We are working to correct this as soon as possible

Tom Brooks
ADSM Server APAR Coordinator
ADSM Server Development