No Single-Player Content
Battlefield 1's single-player campaign is an excellent alternative to the multiplayer portion of the game. Sadly, DICE has left the campaign out of They Shall Not Pass.
In response to a question about the potential for new War Stories in They Shall Note Pass, EA noted that the expansion won't feature any additional War Stories. The official change log for the March update and They Shall Not Pass confirms the bad news.
This is unfortunate but it was expected. The first DLC, and perhaps the rest of DICE's upcoming Battlefield 1 DLC, will focus on multiplayer.
Those of you looking for more single-player Battlefield 1 content should leave feedback for the company on its forums and keep those fingers crossed.