Battlefield 1 Premium Trials begins this month.
Premium Trials, which lets players who don't own a Battlefield 1 Premium Pass play on maps they normally wouldn't have access to, starts with the release of this month's new night map Prise de Tahure.
Here's how it works: if you don't own a Battlefield 1 Premium Pass, you can use Premium Trials to play Prise de Tahure along with Nivelle Nights and the four other maps from the They Shall Not Pass expansion. These Premium Trials are events, developer DICE said in a post on Battlefield.com, so are time limited. There will be another event after this first one but before Gamescom in August, then another in September. So, all players will have the chance to play on previously released expansion pack maps - for a limited time.
This is important because Battlefield 1 currently splits its userbase between those who do pay for expansions and those who do not. Fans have considered this an issue for some time, and are calling on publisher EA to change the way Battlefield multiplayer works for future games - particularly in the context of other multiplayer-focused EA shooters.
For example, Titanfall 2 makes all maps free for all players. EA has said it'll do the same for upcoming shooter Star Wars Battlefront 2 (although there's a whiff of pay to win about Star Wars Battlefront 2's microtransactions). The upshot is there's a feeling among Battlefield players that paid maps have had their day - and the hope is the next Battlefield game, presumably Battlefield 5 for release in 2018, will not lock maps behind a paywall.
For now, Battlefield 1 players will have to make do with paying for maps. The In the Name of the Tsar expansion comes out in September, then the third expansion, Turning Tides, comes out in December.