Like you say, they used to post an article every few months on their website for what they would be releasing within the UK. But tbh I don't think they can be bothered anymore, though saying that every now and again AnimeNewsNetwork post their own article about what Crunchyroll will release in the UK. So that's probably the closest thing nowadays to an actual public announcement/press release from Crunchyroll.
As for AOL listings, this is just my hypothetical guess that Crunchyroll sends an email to
@MVM notifying them with a list of titles they will releasing each month. Then whoever oversees the management/update of anime-on-line's website, updates those listings as and when told to.
Lastly as for your query about shield hero season 3, that's not due out in the US until the end of February, so a potential UK release barring any delays won't happen until at the earliest, sometime between March and May.