In Destiny 1, as you gained experience, your sub-classes advanced as well to allow you to unlock new abilities. In Destiny 2, they changed this to where you use upgrade points in order to unlock new abilities.
I started out as a Warlock, which begins you off with the Dawnblade sub-classes, but unfortunately, without realizing that the Stormcaller sub-classes isn't unlocked until later, I spent every upgrade point so far. Now I am wanting to save my upgrade points until I unlock Stormcaller, but I am also wanting to advance in the other sub-classes afterwards.
Based on this article, it mentions there are a multiple ways to getting upgrade points, but it doesn't go into detail of every possible way
Upgrade Points are earned in a variety of ways, including completing Adventures, but the easiest way is by leveling up
What are all of the ways to obtain upgrade points to advance in your sub-classes?
Best Answer
The two ways as far as I can tell: (After maxing my warlock subclasses)
1) Leveling up, you'll continue to earn them this way past 20 until you've filled out all the skills in a class.
2) Doing adventures that have upgrade points as a reward. If you've fully upgrading each subclass these rewards will change, usually into blue engrams in my experience.
3) If you do meditations and still need upgrade points you can get them from those.