Hmmm....wow, what an ass they've been to you.
GAME.UK online in my honest opinion are ignorant basterds! They're unforgiving and relentlessly ignorant. And yet when they make the mistakes they still hold their noses up.
I've had cancellations by them before without giving me a chance to fix anything up.
Now according to amazon, the game itself weighs around 8 ounces [235grams], with all the contents and the thick A4 size art book it looks like it'll most likely weight heavier than 1kg?? S: But I"m not 100% on that.
It's up to you though, I'll keep it until 10 days before release, I wouldn't want them to charge me 7 days before release if they permit it to be shipped here.