I plan to go to Alishan during the National Day (some day from October 1st to 5th). I understand that it is difficult to buy tickets for the small forest train from Chiayi to Alishan for sightseeing? Is it only available in Chiayi? If I go to Kaohsiung or other cities first, can I buy it elsewhere first? In the same way, is it difficult to buy train tickets for watching the sunrise on the Zhushan branch line during the above-mentioned period? Experienced friends please advise, thank you!