The tickets in the packages don't become active until check in day. At that time you can move an unused ticket to a dummy family member profile. If you try before that you will get the message the PP posted.
You can purchase the 1 day ticket, have it linked to your band, and BEFORE you enter a park reassign the 4 day ticket. CM's will tell you they can prioritize the tickets but I'm always worrying that my
MDE account will be the glitch of the day and not get it right. Moving the unused ticket to another "person" is fool proof. You FP res should not drop as long as there are active tickets in your MDE account. I know they can fix any errors but I don't want to waste time at customer service to do it, would rather just tap and enter the park with no worries.
And for reference, you can move these unused tickets back and forth to yourself for advance FP purposes and then back to the dummy profile as long as they are unused. Would assume that after the expiration date (I currently have some from last year that expire 12/31/18) they could be used only as a credit and maybe not good for advanced FP anymore, need to wait and see on that.
It's not really complicated, just add a placeholder name to your "friends and family" list, then reassign the ticket. Takes only a minute.