Does the BahnCard 25 and 50, 2nd class = 1st class special offer also apply if the outward journey is in May 2026 but the return journey is not until June 2026?

No, the special offer is only available for travel between 1 May and 31 May 2026. The return journey must also be made by 31 May 2026 at the latest. If you would like to travel back in June 2026, you will need to buy two separate tickets for the outward and return journeys.