Hi Qinqin,
We release Dataverse quarterly. That is, we plan to release quarterly. Sometimes we additionally ship what we call a "hotfix release" (e.g. 6.10.1) if there's some sort of critical bug.
As for the historical data, honestly, AI is not a bad way to get it. You can `git clone`
https://github.com/IQSS/dataverse and ask AI to tell you about the tags, which map to releases, and when they were made.
I'll go ahead and attach the data for you from AI (Claude). And a fun timeline plot it made for me. And the code it wrote.
You could also get this data from the GitHub API, but this is an exercise for the reader.
I hope this helps!
Phil