Revision is an essential part in gaining your A-Level and as a result due time and consideration should be given to it.
However, history is not all about learning facts it’s about understanding. Although, learning lots of facts in exams is helpful it is how you utilise these facts which is important. For example, if you know that Martin Luther nailed his 95 theses to the door of the castle chapel in Wittenberg but don't understand its context in a wider narrative of events, you won't understand its significance. This will severely limit your ability to gain higher marks.
Everyone approaches revision in their own way but it is important to give yourself enough time to revise and ensure your technique works. As a result, it’s never too soon to start revising!