One thing to keep in mind, and what hasn't been mentioned so far, is that the ground exams *expire* if you don't pass your skills test within a certain amount of time.
You've got plenty time to look up the details in LASORS so I'm not going to track them down for you now, but if you plan (due to finances) to do your PPL lessons once a week, it's something that you should take into consideration. If you do them too early you might find yourself in the situation that you need to do them all over again by the time you're ready for your test.
If you are going to do a three-week program in Canada or the USA, this is obviously not relevant. In that case get them all done beforehand, if possible.