ok I changed my plans.
I will arrive at TPE airport around Jan23 6am. Then I will have a layover until around midnight.
My plan is to store my bag at the airport.
Then get on a train and visit another city, (ie. Taichung).
Then return to Taipei in the afternoon
And then head to the airport in the evening.
Get my bag, visit the lounge, shower, and move on.
My main interest will be seeing the typical sights of Taichung, then various markets or night markets, seeing any CNY decorations, etc in Taichung or Taipei.
My main question, is it necessary to book the trains in advance? I can't predict if my flight will be delayed.