https://www.livescience.com/space/space-exploration/astronauts-stranded-in-space-due-to-multiple-issues-with-boeings-starliner-and-the-window-for-a-return-flight-is-closing
https://www.livescience.com/space/space-exploration/astronauts-stranded-in-space-due-to-multiple-issues-with-boeings-starliner-and-the-window-for-a-return-flight-is-closing
The article says the 45 day window is due to fuel limitations with Starliner, so at that point I'd imagine they'd un-dock it and de-orbit without crew. Regardless they wouldn't leave the astronauts to die (I hope) and would mount a rescue mission.