I would suggest starting this season doing one or two more training level events and then move up to prelim at Full Gallop. They have 3 events in the next few months anyway, so my suggestion would be to go to their first event in a few weeks at training level (if you're ready to compete now) and then if you feel comfortable and your trainer feels you're ready move up to prelim at the next Full Gallop. I was just there schooling a few days ago and it looks fairly welcoming for prelim.
Just be careful with your horse. While I know you mentioned in his profile he's competed at that level before, I noticed looking at his pictures that he really hangs his forearms and while it looks like he jumps high enough that it's not an issue, it's not exactly the safest jumping style and could lead to a nasty accident if he misjudges a fence's height or something. Makes me nervous and worried for your safety, is all. :) Good luck! If you're at Full Gallop any time until April showing I'll probably be there as well.