Assuming you refer to the overall time for discussing this case - I guess the author will be able to give you a rough idea and some orientation.
However, for case interview prep I'd rather say you need to ensure to have a laser-sharp analysis with a rigorously structured approach. I will decide as an interviewer where to go deep and have a more elaborate discussion as opposed to "solving" the case at the end.
From a slighly simplistic perspective, the discussion between you and the interviewer about specific parts of the case are more relevant for evaluation, than finding "some" solution at the end. So the overall time depends mostly on how deep I want to go in which areas of the case, and it's a result of our direct interaction and thus less of the specific case and sample solution at hand.
Hope that helps as an additional insight for your prep - if so, please be so kind and give it a thumbs-up with the green upvote button below!