I also would like to see the possibility to delete a release via the UI. Using command-line is possible, but hard to apply. It is easy to make mistakes, and is time consuming. You need to figure out first how it is working. When developers creating multiple (internal) releases for test-purposes, the number of releases growths. A clean-up of the releases by deleting older and unused versions is preferred. This should be possible via UI.
question how to delete a release is asked several times on the forums. Par example: How to delete a release? - #19 by arcsi
Matt set the status to Completed
This feature is now live as of version 18.11.0 of the dashboard. You can find it in the Modify dropdown of the releases table or on the Settings page for a release. Along with this feature getting shipped, it is also now possible to delete fleets that were previously unable to be deleted as a result of having had a device moved to another fleet and that device still running the old fleet’s release. Thank you to everyone who voted for this feature, we look forward to hearing more of your feedback!