Probably not as soon as you’d like, but not as late as you might think.
You’ll have it before you see the film at the very least. 
I’d add that I believe preorder customers will be getting the pdf as soon as we have that completely finalised, and that shouldn’t be too far away. Although hardcopy books will be a little while yet.
Sorry not to be more precise. We have a date we’re working to but there is always a lot that can go wrong and we don’t want to raise expectations just in case.