It's easy for a text we've selected, whether basal or trade book, to extend beyond the ideal time frame of a focus lesson. So yes, breaking it up over the course of a few focus lessons is a fine alternative. If you aren't constrained by the use of a basal, we love to use picture books with all age groups. There are beautifully written and illustrated titles that lend themselves well to teaching all the Cafe strategies.

Since students typically have a bit more stamina for the first focus lesson, you may be able to extend it a bit past the recommended minutes (we like to stick with a focus lesson that matches the average age of our audience). If your strategy lesson is anchored to a text and you don't stop too often during the reading of the text, students can stay engaged a bit longer because of the cadence of the story.