Release start date can currently only be mapped 1-way from Aha! to Jira (or any development system.) This is because that date used to be calculated based on features and phases in the release.
Now that this date is set manually, it should be possible to map these 2-way so they can be imported and/or updated from the development system.
I'd also like to see release end date to be mappable to Dev Ops. Since we work in scrum, our release date range is our 2 week sprint. Having the internal/external release date mappable to Dev Ops doesn't make sense, since that is when the features would be shipped. Not when the sprint ends.