While in Early Access, Dota Underlords is in a constant state of flux and Valve have again changed the ranking system.
For those good enough to be in the Lord of White Spire ranking, they're now using the well-known Elo rating system, so the number of points gained or lost now depends on the skill of your opponents. Why the switch? As Valve said, the Lords of White Spire leaderboard ended up being a list of who played the most instead of the best so they're hoping this will solve it and be a little more fair to those who don't play all the time.
Other ranks don't seem to be affected by this change, as Valve think they have a good enough balance for those ranked from Upstart through to Big Boss. You can see the main changelog here, with their explanation on the rank changes here.
Dota Underlords still seems to be doing very well on Steam. It's regularly hitting over fifty thousand players a day, although going by SteamDB graphs there's a clear decline over time. That said, it's pretty skewed due to the massive player influx at the start.
What is great, is to see a team at Valve keep in constant communication with the community, I imagine that has helped Underlords quite a lot.
Are you enjoying Underlords? What are you hoping they do with it next? Let everyone know in the comments.