The last time I did this it was 15000 miles. Luckily the next DB branch was 50-60 km away and I just had to bear with calls in the evening. I got a full 'profile' what to do and politely declined. Two months later the sales guy finally gave up and closed my file. The miles showed a week later.

I have to update the address on my db sparcard this week since I moved to MUC. Let me see if I can get 7500 miles for that visit