*This is very spoiler heavy so please stop reading if you haven't proceeded this far in the game*

On my first run through the game, I am playing a very agreeable, high charisma, play all sides against the middle, kind of guy. So, I ended up being a member of the Minute Men, the Brotherhood, the Railroad, and finally, the Institute (family comes first!).

So, maybe because of this, when I arrived at the Battle for Bunker Hill mission, and did not inform the Railroad or the Brotherhood about the Institutes mission regarding the 4 synth's, I fully expected to go into that fight with both the Railroad and Brotherhood being aggressive towards me (seeing as I was fighting along side the Synths, and, you know, killing every Brotherhood and Railroad member I saw).

This was not the case, everyone in that mission was neutral to me even as I blasted them from point blank range (they kept their attention on the Synths as I was standing right next to them).

I see that in the game design, it is the next mission that is the "point of no return" from the Brotherhood perspective at least, but I haven't received a message indicating the Railroad is after me as well (although they definitely should be).

Just an odd bug I ran into that made a late-ish mission a walk through (literally - I walked through the mission and no one shot at me as I was killing them).

Of course, given that you are allowed options of changing sides after this mission maybe it was not a bug or an oversight. If that is the case then the faction KOS "point of no return" should be slightly earlier in the story line given that there will be people (like me) that will play all sides as long as there is a benefit to doing so (and this seems to confuse the hell out of the game mechanics).