Android & Docker on Ubuntu 20.04 update! 
Notable changes:
- Security Patches
To select these Stacks you just have to open your app on bitrise.io,
go to the Workflow tab (Workflow Editor), and on the Stack tab select the Android & Docker on Ubuntu 20.04 or Android & Docker on Ubuntu 20.04 option and your next build will start on the corresponding stack.
*Note: you can now select separate stacks for separate workflows!
Read more at: https://blog.bitrise.io/per-workflow-stack-selection-is-here
You can find the system reports here:
https://github.com/bitrise-io/bitrise.io/blob/master/system_reports/LINUX/linux-docker-android-20.04.log
If you’d like to add additional tools to be pre-installed you can find the instructions on GitHub, for both the Linux and for the macOS stacks.
Information about Stack types & update schedules can be found here: discuss.bitrise.io/t/281
Happy Building! 