Route for Zhangjiajie Grand Canyon Ticket A vs B/C

Hi,
1. Is the Ticket type "A" for Grand Canyon (only) sold on the spot / no need booking before?
2. Is it a different route down to the canyon with ticket type A vs B/C?
3. If I'm able to book tickets for a combine trip glass bridge + grand canyon, how does the route goes, will I return back from the glass bridge and get my camera back before the canyon, or the route keeps continuing to the canyon leaving my camera later on until the end of the whole canyon walk?
thanks