Purchase the Cobb event

Dear team, dear all, 

I would be obligated if someone could help. 

I want to purchase the "conquest" for Cobb with premium rewards, with the price 11,99€ but I'm already in the middle of the basic rewards. 

Anyone knows if I ll purchase for premium rewards, will get all the premium rewards from the beginning, or the rewards will be switched from the point I have stopped from basic rewards to the premium ones?