After completing the game 100%, I found I was unable to upgrade Ravensthorpe to level 6, despite having completed all raids and all pledges. I suspect that the cause of this might be that my final upgrade came from a reputation boost from completing a pledge, rather than from upgrading or constructing a building in Ravensthorpe. So this now presents me with the unique problem of being unable to complete my settlement, despite having done every else the game has to offer.
I did complete the game very much out of order, as I completed every single raid before even completing my first pledge, and while I was still around 100 power. So perhaps this had something to do with it. But since you receive the remainder of the necessary raw materials from several of the pledges, this seems unlikely. I can't say for certain, but is a patch for something like this possible, or will I just have to accept that I won't get the achievement for this?
For any other relevant information, I was on the Xbox One X, and my gamertag is I Astronomer I.