This went up yesterday (apologies if it’s been posted feel free to delete) and it shows a toggle in the PC options for DX12 as well as making comparisons from Ultra > High > Medium > Low settings. BF1 still looks decent @ Low!
Paraphrasing here but DF reckons that “any PC currently coping with FrostBite 3 games should run BF1 just as well”.
http://www.eurogamer.net/articles/digitalfoundry-2016-hands-on-with-battlefield-1-on-pc