i. Substantive usages of αὔριον meaning next day:
On the next day, when he departed.... [Luke 10:35 WEB]
Καὶ ἐπὶ τὴν αὔριον { ἐξελθών ♦ - }....
They laid hands on them, and put them in custody until the next day, for it was now evening. [Acts 4:3 WEB]
Καὶ ἐπέβαλον αὐτοῖς τὰς χεῖρας, καὶ ἔθεντο εἰς τήρησιν εἰς τὴν αὔριον· ἦν γὰρ ἑσπέρα ἤδη.
It happened in the morning.... [Acts 4:5 WEB]
Ἐγένετο δὲ ἐπὶ τὴν αὔριον....
ii. Can the substantive be said to always mean next day (i.e., do the following substantive usages also properly mean next day)?
Therefore don’t be anxious for tomorrow the next day, for tomorrow the next day will be anxious for itself.... [Matthew 6:34 WEB]
Μὴ οὖν μεριμνήσητε εἰς τὴν αὔριον· ἡ γὰρ αὔριον μεριμνήσει { τὰ ♦ - } ἑαυτῆς....
Come now, you who say the ones saying, “Today or tomorrow the next day let’s go into this city....” [James 4:13 WEB]
Ἄγε νῦν οἱ λέγοντες, Σήμερον { καὶ αὔριον πορευσώμεθα ♦ ἢ αὔριον πορευσόμεθα } εἰς τήνδε τὴν πόλιν....Whereas you Who don’t know what your life will be like about tomorrow the next day.... [James 4:14 WEB]
οἵτινες οὐκ ἐπίστασθε τὸ τῆς αὔριον (the of-the-next-day)....
iii. Could Luke 13:33 have been equally written αὔριον καὶ τῇ αὔριον instead of αὔριον καὶ τῇ ἐχομένῃ [ἔχω]?
Nevertheless I must go on my way today and tomorrow and the next day.... [Luke 13:33 WEB]
Πλὴν δεῖ με σήμερον καὶ αὔριον καὶ τῇ ἐχομένῃ αὔριον πορεύεσθαι....