The BahnCard is valid for 12 months. The BahnCard 25/50 at the promotional price is valid for 1 year from the 1st day of validity. Unless you cancel it in text form 4 weeks before the end of the term, the subsequent card is a regular or discounted BahnCard or a senior citizens BahnCard or My BahnCard 1st or 2nd class. Your date of birth will be used to check which BahnCard is the subsequent ticket.