Do i need to replace the iPhone at the store for iPhone upgrade program?

I am doing in-store pickup but I want to take it back home with me to do the transfer and make sure all my 2FA (two-factor authentication) apps are properly transferred over, etc before I return the old (current) phone back in-store to complete the iPhone upgrade. When we do the mail-in kit, it says we have 14 days, so there is a period where we would have both phones are home, but just wondering if this is possible with in-store pickup also. Do I need to replace the iPhone at the store at pickup to walk away with the new one for the iPhone upgrade program?