So I'm doing the first quest "father" gives.

Synth Retention

I show up and the moronic Courser is attacking a band of BOS that have helicoptered in.

Thinking it is a matter of him accidentally hitting one of them I reload and watch more carefully this time.

No.. it is a matter of him attacking them when they were ready and walking away..

So.. No main quest for me I guess..

Thanks Bethesda.. Guess I will go play some Morrowind.

=edit=

I am BOS.

I did reload -again- and ignored the Courser. Walked with the BOS. Aiding them as needed.. Until I was about a mile away. I then jogged back and carried on with the quest.

Posting this in case anyone else has this bug.