Huanglong to Jiuzhaigou or to Songpan

Hi,

I am planning on going to both Jiuzhaigou and HL after a few days in Songpan.
I have seen there are buses from Songpan and Jiuzhaigou to HL but how about leaving from HL?
Are there buses to Songpan and/or Jiuzhaigou? What time are them at? I would like to go to HL in the early morning and leave in the afternoon. Are any buses leaving around 2 or 3 pm at least?

Thank you.