Ahhh! Who do I trust?!?

Right, so I'm taking the new 9-1 AQA GCSE Geography specification, but I'm really confused on the content I'm supposed to learn. I have four different sources of information, however, they all seem to be misleading! Let's use the topic of composite and shield volcanoes as an example. My Geography teacher was teaching us about composite and shield volcanoes, but then I looked at the specification and it wasn't on there! However, it was on the old specification, so I thought she was just teaching the old specification because that's what she knew best. Then there's my Geography study book (which has been approved by AQA might I add), which gives information about composite and shield volcanoes, however, my CGP revision guide has nothing about them. This isn't the only topic like this, I was just giving an example. So, who do I trust? My teacher and my AQA approved study book, or the AQA specification and the CGP revision guide? Please help!

you might have the wrong revision guide, you could have bought the A* to G revision guide. Trust your teachers and the AQA approved study book.

double post

I definitely haven't, it clearly states it is the 9-1 guide on the front. D:
Edit: It also matches with the structure of the new course, so it's not a printing error or something

I'll see if I can e-mail AQA or something. Thanks!