Good news - no more complications with used question on the Start Test page. You can now retake all of your previous tests from the Revision & Statistics page.
For each test, you will have one retake opportunity - this means that each of your tests can be taken twice, regardless of how many questions you answered correctly or incorrectly.
Just click on Retake next to the test you wish to take again on the Revision & Statistics page to take advantage of this new feature.
What does this mean in practice?
1. Your used questions are not lost - you can now retake all of your previous tests in full one additional time.
2. Let's say you purchased 200 verbal reasoning questions. You completed 5 tests, each with 20 questions (you used 100 questions) and answered 50% correctly. In the old system, you would have 100 new questions left, and 50 used questions as well - those 50 that you answered incorrectly.
3. In the new system, you still have 100 new questions left, and you also have the opportunity to retake all your previous tests - this means that you can reuse all 100 used questions one more time.