Right. A few months ago Rovio released Angry Birds Halloween, much to the world's surprise. Less surprising was the news that followed a few weeks later: a Christmas edition would be along in due course.

Except, we later learned, it wouldn't be a separate Christmas edition. It would be a free update, rather like the ones Doodle Jump gets. Angry Birds Halloween would cease to exist, and Angry Birds Christmas would replace it. Got that?

No, you haven't. If you're looking for Angry Birds Christmas on the App Store or the Android Market you won't find anything. Rovio has decided to call Halloween/Christmas edition of Angry Birds Angry Birds Seasons, of which Angry Birds Halloween is a part.

According to the press release: "Season’s Greetings consists of 25 daily surprises for fans of Angry Birds to enjoy while counting down the days until Christmas. Included in the game is also the 45-level Halloween special edition, now packaged as a separate episode called Trick Or Treat."

Angry Birds Season is now available on Android Market, and – according to Rovio Mobile in conversation with Twitterer e-martin - it should be on the App Store “within hours.”

If you already own Angry Birds Halloween, Seasons will arrive as a free update. Otherwise it'll cost you 59p / 99c on iPhone and £1.19 / $1.99 on iPad.

Thanks, Charles Clout