I'm not sure whether to buy this news as the original source has poofed itself right out of existence but since in the never-ending game of telephone that is "Breaking News!" on the internet it took me several links to find the original source no longer exists I doubt it'll stop most places from reporting it (and anyway, it allows me to post Shirtless Michael Biehn Pictures, so who cares, we all win no matter what), here goes -- supposedly Michael Biehn said on Instagram that he won't be able to go to a UK Comic-Con because he's gonna be way too busy shooting Neill Blomkamp's Alien movie. His Instagram no longer exists, but supposedly it did, as of recently, and he said that.
I hope it is all true! Biehn's character Hicks, who (ancient-spoiler-alert) was killed at the start of the third movie much to everybody's chagrin, was featured in the art-work that Blomkamp posted that got him the directing gig, so everybody is wondering if (and you know, HOW) that might happen. But Biehn's terrific, it'd be lovely to see him reprise the role.