Should I book Dolphin at higher rate now?

[RedE2Go]

I'm hoping for a room at the Dolphin March 2003 at a teacher rate. They aren't showing any teacher rates yet. Can I book the room at the much higher rate, then change it with no penalty to the teacher rate if/when it comes out? My husband doens't think I can do that. I'm afraid if I wait too long to book anything, I'll wind up without anything. But I can't afford the Dolphin without that discount. I hate having to go when rates are at a premium, but we aren't flexible in that area, unfortunately. Thanks for any help.