how to get to Zhangzhou?

So you are setting off from Xiamen, right? Now you can use BUS instead.
1. Take a direct bus from Hubinnan Long-distance Bus Station to Yunshuiyao. Two buses are scheduled daily, at 08:00 and 12:10. Their final stop is Meilin Town, so ask the driver to drop you off at Yunshuiyao. Then you can walk to the accommodation.

2. Take a bus to Nanjing first (CNY33) at Hubinnan Bus Station and they are scheduled from 07:00 to 17:50. Then transfer to another bus to Yunshuyao at a cost of CNY17 and walk to the homestay.

Oh thank you, that was really useful! Which connection would be faster?

In the meantime I learned that may be the trains to Nanjing (which would be the fasted connection) are not yet booked, but that they will start to be sold only 40 days before. It is tough quite puzzling, since some other trains on the same day but at different time could be purchached. Would you please know how is it? Thanks!

Oh, China Railway Corporation is adjusting the train timetable recently. Maybe that's why some of the tickets are not available yet. You may keep an eye on it and they can turn available anytime.