Question about future vacation requests

This is a bit specific but wondering if anyone has experienced something like this… I’m a huge rugby fan and I want to go to the World Cup in Australia in the first or second week of Nov 2027… only problem is the tickets go on sale in Feb, and obviously the match is end of march.

Now I would be a PGY-2 when I’d leave for this trip, and would book everything so I could go for only a week.

Would it be unreasonable to book the tickets and then once I match give them the heads up that I’d like to schedule one of my weeks of vacation for that week?