Thayer's
STRONGS NT 2259: ἡνίκαἡνίκα, a relative adverb of time (from
Homer down),
at which time; when: followed by the present indicative, of a thing that actually takes place,
2 Corinthians 3:15 R G; followed by
ἄν with subjunctive present,
whensoever: ibid.
L T Tr WH; followed by
ἄν and the aorist subjunctive with the force of the Latin future perfect,
at length when (whensoever it shall have etc.):
2 Corinthians 3:16;
Exodus 1:10;
Deuteronomy 7:12; Judith 14:2. (On its construction see
Winers Grammar, 296f (278f); 308 (289);
Buttmann, § 139, 33.)