Hi

Do you need to have joined the BoS to get the Shadow of Steel quest when the airship shows up? I didn't return to Cambridge Police Station after the Arcjet mission (forgot) and I got the Shadow of Steel quest when the airship appears, I listen to the radio frequency and get the quest to return to Cambridge, however when I arrive the Arcjet quest completes and Danse talks about how I helped yada yada... I decline to join again and the Shadow of Steel quest just disappears. Have I managed to glitch things or was I just not supposed to get the Shadow of Steel quest if I had returned to Cambridge and declined the invitation to join back at the Arcjet mission?

Thanks

I think you're supposed to say you'll join, that way you get to take the ride onto the Prydwen. Even then, you can still join another faction.

The point where you cannot join any other factions should you proceed to commit yourself to a certain faction, you'll get a dialogue box on your screen just before the quest, asking you to confirm if you wish to continue.