As we were travelling during the festive seasons of New Year, we decided to buy our TRA train tickets on the very 1st day we arrived. This was advised by the information counter personnel at the airport. As for THSR, it was alright to buy on the spot as there weren’t many people travelling by THSR due to the higher train fares.
To make the job easier for the ticketing personnel, my friend had listed all the dates and timings of the train that we need. This really shortened the time as we did not need to ask for the timings. So, one word of advice, if you are travelling on TRA trains very frequently, it’ll be a good idea to check the timings online before you fly off, decide on the timings you need and buy all the tickets you need on the 1st day you arrive.
We managed to buy most of the tickets we wanted except for the tickets on 01 Jan. There were no more reserved seat tickets available and we ended up buying free seating tickets, which means we had to stand and move around to look for empty seats, and most of the time there weren’t many. So, this kind of tickets are also called “standing tickets” (站票).