Why is this going to Crown Court? The obvious answer is that she herself asked for her case to be sent there, for trial by jury. It's only a minor abh, so I can't see that the prosecution would ever want it tried there. And you say she has no previous; it may be that she, pleading not guilty, thought, or was advised, that her prospects of an acquittal are better with a jury than with magistrates trying the case.
Can't see how, on the facts you give and she having no previous, she is it at any risk of going to prison