I'd been there at the end of this year along for testing a hiking road, everywhere are evergreen,good for year round visiting. Hostel is like B&B but they don't serve breakfast as a lot of Chinese restaurant are available to serve breakfast nearby. No western food availabel as this mountain located in the very centre of Chinese hilly area.
Very easy to take G Train from Beijing,Shanghai,Hangzhou here,the arrival train station is also called Yandangshan, 20minutes by local bus or cab to Chaoyangdong Parking lot where the hostel located and easy to go by shuttle bus for visiting. 2day visiting is enough if you prepare will with it. No need to hire whole day bus or car service, shuttle bus are very easy to take(you may need an English guide as there only Chinese service available)