Taking things literally - but knows what we mean...?

My daughter is 6 and has been referred for an autism assessment by the SENCO at school. One major trait which everyone sees is her "literal thinking".

Some examples: 

- "I don't need an 'extra hand' I already have 2."

- "I've counted 60 seconds and you're not ready, so you 'lied' about 'in n a minute'."

- "Everyone in the world doesn't have a bookbag so how can 'everyone' bring their bookbags in tomorrow?"

Etc... 

Now I'm not disputing that she may be autistic, it's been on my radar for a while as her Dad is autistic, she flaps her hands/stims, it is very difficult to have a conversation with her that doesn't become tangential and she has no filter and is extremely blunt! But to me the literalness seems like cheekiness a lot of the time. She knows when you ask her what is meant by 'do you need a hand?' etc by she still comments literally every time. 

Is there a line? I would have expected her not to understand the meaning if this was truly an autistic trait, and I'm not sure how to deal with it right now. Does anyone have any advice? Does anyone or their child react the same even though they do have an understanding of the intended meaning? I'm struggling a bit to understand.

Thank you