Thanks for all your replies! What surprised me is that the price went up - I understand that the "Insure My Tesla" offer doesn't include the (regular) yearly discount in pricing due to driving without causing any damage. But as it stands right now, Codan would treat me (even if only 3%) worse than somebody walking in from the street (the original offer of 9945 is still advertised on their website). I will call and ask.
EDIT: I finally got around to call: there was a systems mistake. The will provide the previous price again. So if you got a strange increase in your insurance, call the "Insure my Tesla" hotline. Overall I would like to recommend Codan, I have good experiences with them.