I found a sentence in my grammar book.

Is there any difference between two sentences?

    Don't phone Ann now. She'll be busy now. 

Here is my concern; There are 'will' and 'now' in a sentence.

'will' is for the action in the future.

But in this case, it talk about present.

Is it the same as 'She is busy now.'

Can I say that in this situation?

Please tell me the reason.

Thank you for your time