Date (happened)
c. 1950 (probable)
"a few weeks later", told in Whom Do Seek 4 1 68 (nid 1935)
Told / reported
1 April 1968
passage 549398 (lecture nid 1935 'Whom Do Seek 4 1 68'), delivery claim 1968-04-01 exact/certain (title dateline, corroborated internally)
Neville sailed (and elsewhere says flew) to Barbados with his wife and daughter for a few months after giving Sam the instruction, and on returning to New York the family gathered the first night for dinner at home, where Neville made a round of martinis and Sam told what had happened.