The MVSGet or MVSPut subcommand fails when transferring a physical sequential extended format data set

When the source data set is of physical sequential extended format, the target data set is allocated as if the DSNTYPE with SYSTEM value was configured. If the system default DSNTYPE value is not EXTREQ or EXTPREF, the source data set might exceed the architecture size limit of the system default DSNTYPE, and the transfer fails.