Homeric Constructions.—In Homer the imperfect in unreal conditions refers only to past time. The apodosis may have κέ or ἄν with the optative.
a. The present unreal condition with εἰ with the optative in the protasis and ἄν with the optative in the apodosis (in form like a less vivid future condition in Attic) is very rare (Ψ 274). In B 80, Ω 220 we have a combination of a past protasis (imperfect or aorist indicative) with present apodosis (with κέν and the optative).
b. Past unreal conditions have, in the protasis, the imperfect or aorist indicative; in the apodosis, either the imperfect or aorist indicative with ἄν or κέ or the aorist or present optative with κέ. Thus, καί νύ κεν ἔνθ' ἀπόλοιτο . . . Αἰνεία_ς, εἰ μὴ ἄρ' ὀξὺ νόησε . . . Ἀφροδί_τη
Herbert Weir Smyth [n.d.], A Greek Grammar for Colleges; Machine readable text [info] [word count] [Smyth].