I believe you have until it ships to cancel.
I was and am still on the fence about the S6. I have a coworker willing to pay me $200 for my Al S4. I was going to get another Al with the new braided blue band. Doesn't seem like too bad of a deal...
Yeah, managed to get it cancelled. Will probably get it eventually. Have a $250 that should be coming sometime next month for joining AT&T. May use that and trade in my watch. Also want to get the iPad though so that’s why I was on the fence