Ya, thanks Lex, it must be. Maybe a variant. Now I see that LSJ says ἀλλά in one form is: “2. in the apodosis[my emphasis] of hypothetical sentences, still, at least, “εἴπερ γάρ τε . . ἀλλά τε”.”
No, I agree it must be a typo. I thought you were answering the question by saying it is the plural of apodosis. Now I see it was YOU who suggested it might be a typo. Sorry.