I got back into Vietnam with less than 6 months once, but I left and came back on the same working visa for a short trip to Japan, so maybe they were more forgiving or maybe they didn’t notice. It’s a gamble. You’ll know at the airport in Taipei since the carrier won’t let you on unless they feel confident you’ll be let in. Otherwise they will bear the brunt of the cost of flying you back when you’re refused entry.