We examine our exams for opportunities to improve our exams once a quarter, and we make changes as necessary. We do minor, clarifying updates on the fly, but substantive changes to the exams are made rarely and will be clearly communicated well before they are added to the exam.
The best way to be sure you've studied for the current version of the exam is to visit the landing pages for each exam. We will update that page with the dates of major updates and the version of the product we test to.