https://www.polygon.com/2018/4/19/17258146/destiny-2-power-cap-expansion-2-warmind-bungie

In Bungie’s weekly update, Destiny 2 senior designer Daniel Auchenpaugh talked about how the power level grind will be changing in Warmind, Destiny 2’s second expansion. In short, it’s going to be a lot harder to max our your Guardian’s power level come May.

Auchenpaugh said that Destiny 2’s public events won’t be nearly as lucrative as they have been, and that clan engrams won’t help players progress on their own. Warmind will have a soft cap of 340, meaning that players will be able to jump up only 10 power levels from Curse of Osiris’ max with open-world drops. However, the hard cap for Warmind is 380.