Major Description
MVSFTPEntryParser doesn't support Record Formats of U and returns `null` for them.
Example FTP output:
Volume Unit Referred Ext Used Recfm Lrecl BlkSz Dsorg Dsname
VVVVVV 3390 2020/04/18 1 60 U 32760 32760 PO NAME
This is a ftp on the zOS which is reporting a MVS FTP and the list of record formats can be found at https://www.ibm.com/support/knowledgecenter/zosbasics/com.ibm.zos.zconcepts/zconcepts_159.htm .