I would usually have linked the official website, but that's been gendered to unreadability, so this article will have to make due:
https://www.spiegel.de/auto/bvg-hvv-mvv-und-co-wer-ein-oepnv-abo-hat-darf-im-september-damit-auch-in-anderen-staedten-fahren-a-9ee1bb17-40a0-481b-9536-7a84325804ae>Sie gilt demnach in über 95 Prozent aller Tarif- und Verkehrsverbünde.>95 ProzentLooks like a recipe for disaster to be honest. Also, aren't there railway lines outside any Verbund?
This will probably ultimately end in quite a few "erhöhte Beförderungsentgelte", and really bad press for public transit.
