I recreated all our old distribution lists as edirectory groups, added members that were listed in the distribution list when viewed via the address book.
GW admin portal, sync'd them via the directory association.

details of a group shows that it is now sync:
LDAP DN: cn=\#Smith_Bldg_List,ou=Distribution_Lists,ou=GROU PWISE,o=BCSC1
Directory: BCSC1
LDAP GUID: cbf387b1-352f-430e-0caa-b187f3cb2f35

However, changes are not being automatically synchronized from eDirectory to GW.
I can manually sync the group in GW and it will then match the eDir group.

Did I miss creating a task for automatically synching from eDir to GW?