Before you book your first sitting, it pays to understand the clock you are starting. The short version of the EASA rules (FCL.025): - You must pass all theory exams within 18 months, counted from the end of the calendar month in which you first attempted an examination. - You have a maximum of 6 sittings to get through them. - Each subject allows a maximum of 4 attempts. - The pass mark is 75 percent in each subject. Practical consequences people often learn the hard way: - Do not sit your first exams before the rest of your study plan is realistic. The 18-month clock does not pause for a busy season at work. - Group subjects into sittings deliberately. Burning a sitting on a single subject early leaves you less flexibility later. - Test centre availability varies a lot by country and season, so book ahead of when you want to sit. These rules have details and national variations that matter, so always confirm the current requirements with your ATO and your national aviation authority before booking anything. How did you group your subjects into sittings, and would you do it the same way again? Which authority and test centre did you use, and how was the experience?