As the release date changes, it's hard to recreate history to figure out what the original date was along with interim dates and the final release date. It's also hard to remember the reasons for a change when it's several months later. I'd like a way to see the history of the Release dates. This is in the Activity list but there's no easy way to extract and organize it. We've created a customer field for PO's to enter changes and the reasons but I would prefer something that's more automated and less prone to forgetful PO's. If the Activity list had a way to filter/query specific items like a Release date change and there was a way to add a comment, that would be preferred over a Custom field.
The Release page has an option to view the history of changes, where it can be possible to view the original date. This can be accessed through the Actions menu on the Release detail page (as shown on the screenshot).
The idea description had mentioned an activity list (though its unclear as to whether you were referring to the "My activity" page vs. this History feature.
Through the History feature, you should be able to find the information that you are looking for. At this time, we do not have plans to add new filters/queries on Activity features, but hope that this feature can help. We hope you can understand.