Got off the phone with them. Pretty much the same copy pasting from the emails.
Went something along these lines.
Why do you show one product and sell another with a sponsor?
"Of course the Inter shop will sell with the sponsor, only Nike can sell it without"
Why did you start receiving orders earlier if shipping wouldn't commence immediately and pending a change?
"We were merely collecting orders to estimate demand".
I don't want the shirt with the sponsor, so just don't send it, saves everyone the trouble.
"At this stage it cannot be done".
But I don't want it..
"Maybe you will change your mind" (seriously, he said that

)
I'll ship it right back, this was very unprofessional.
"Either way, it will come to you, you decide what you want to do with it once it arrives".
A few more anecdotes as well. To be honest, the interaction made me less pissed because it makes you realize who you have to deal with