A person came to shul on Friday afternoon to daven Mincha. By accident he started saying the Friday night S”E (Maariv) instead of the weekday Mincha. What should he do – continue with the Friday night S”E and then repeat it as tashlumim for the Mincha that he missed, or switch back to the weekday brachas?
Since he davened maariv by mistake, he didn’t mean to be mekabel Shabbos, therefore it is still Friday for him. He should stop davening the Shabbos davening and continue with mincha.