In the filters of "First Question" queue, it is suggesting 14.04.
As some comments have already mentioned, it's probably not a bug as it's just some selection of popular tags.
If something needs to be changed here, it should probably be a separate feature request.
Having said that, I think it's good to show outdated tags in the First questions queue. For example, if you filter on 14.04 and find questions about them, there's a high chance they will be off-topic (please don't robo-vote-to-close, though!).
When you're creating a new question, it shows different tags, but if I remember correctly, moderators have control over what to show there (or not show?).