BSYR476E Invalid value. The Source Stogroup selection field should be either Y, U, or N.

Explanation
The value entered in the Source Stogroup selection field is
invalid. You must specify either a Y to enter a new Source Stogroup selection, a U to update the
Source Stogroup selection, or an N to specify that a Source Stogroup selection does not
exist.

User response
Enter a valid value.