That's not the case with [1], for example. They allow pausing (and then canceling) the subscription any time before the last day of the month. It works as advertised in my experience.
[2] seems to be offering the same, but I haven't tried it myself. [3] looks interesting too.
See, this is not making me feel good about the deutchland ticket.
My understanding is that the Bavarian day ticket can still be purchased as a piece of paper from a kiosk at the station and we would print our names on it (2 adults, 3 kids). This seems so much easier than worrying about starting and stopping a subscription!
[2] seems to be offering the same, but I haven't tried it myself. [3] looks interesting too.
[1] https://www.ticket-plus.app/en/
[2] https://www.mopla.solutions/de/tickets/deutschlandticket
[3] https://deutschland-ticket.store/autobus-oberbayern?lang=en