I think so.
In Aus, you are not even allowed to compete until the horse is 5, and even then at restricted distance and pace. I would be very suprised if they dont have similar regulations where you are.
I honestly dont think you need to start conditioning any sooner than 6 months prior to the first ride, and this conditioning should be done in a progressive manor. This will give you more than adequite time to get your horse ready.
Spend the time between now and then giving your horse a good education on the flat, coupled with very easy rides out.