ישעיהו ה:יא פירוש: רש״י ואבן עזרא

They sit until late in the evening to drink wine at night.

משכימי That rise up early. Status constructus, although followed by the preposition ב; comp. השכוני באהלים that dwell in tents (Judg. 8:11);

wine inflames them It burns in them.