That being said, there is still a threshold for the minimum amount of time you need to spend on prep to be adequately prepared. But of course, everyone has a different schedule, meaning that the number of hours they’ll reasonably be able to commit per week (while still having a life) could be vastly different.
Our general recommendation is that during the term, you should spend at least two 2.5-hour slots per week (e.g. two afternoons on the weekend) or three 1–1.5-hour slots per week on UCAT study. During the holidays, you should do as much as you absolutely can: think 2 hours in the morning, 2 hours in the afternoon and 1 hour in the evening. The more you can get done during the holidays, the less you’ll need to do during the school year.
The later you start, the more hours you’ll need to do per week in order to get everything done in time. (If you start 1 month before the exam, you’ll need to do around 62–75 hours per week to be test-ready in time for your exam—an impossible task, especially with schoolwork and important mid-year tests!!)
The absolute best way for you to reduce your weekly UCAT study time is to focus on getting most of your prep done during the summer holidays. By completing most of your UCAT preparation during the holidays, your workload during the school year will be a lot lighter, and you can become proficient at the UCAT before Term 1 even starts—this is an amazing advantage to have over the competition, both in terms of your mastery of the UCAT and your ability to put more time and effort into your ATAR.