Child going from dla to pip with autism

What do they ask when you phone to claim pip? I have to do this for my child moving from dla to pip.

I have just got a letter to claim this for my child who has just turned 16. I am dreading this as i have read so many bad things and folk not qualifying for their benefits any longer. I have looked on the site but cant find anything that tells me exactly what they will ask when i phone. Also it states face to face consultations are probable which im dreading. Centres are more than 90 mins away by public transport. I would like to know how parents in my position have got on with claiming this and their outcomes. I would also welcome advice in completing this form as it doesnt seem autism friendly at all

Forgive me Merlin, I have wrongly merged your post with another member's topic! I will ask Gordon to try and sort it out for us!

Meanwhile, the guide that Gordon linked to, in the previous post, explains what you will be asked in the initial phone call.

They are both my questions. Sorry new to this. Have looked at link he has sent but have not found all that they will ask on the phone. I have heard that sometimes they ask about things in detail on the phone and i am afraid that i wont be prepared enough for it..
Also can you tell me when applying for pip, do i need to send all info that i sent originally for dla going way back or when do i send info from? Im very confused and getting anxious about this.