If a DCBE exists and the data set is an extended-format sequential data set, OPEN stores the number of stripes of the data set in the DCBE (DCBENSTR) before the OPEN exit is called. If a DCBE exists and the data set is not an extended-format data set, OPEN stores 0 in DCBENSTR.

For a partial release request on an extended-format sequential data set, CLOSE performs a partial release on each stripe. If the data set has only one stripe, the space is released only on the current volume. After the partial release, the size of some stripes can differ slightly from others. This difference is, at most, only one track or cylinder.