Thank you for your answers. Now I half-remember having read some of these pages years ago...
And having giggled at a particularly funny post, "They just can't admit that Bishop did it", and the banner another member did, Easter Egg fashion, with a joking Bishop carrying the egg wrapped like a present or something.
Personally I find it way less terrible than the changed shape of the cryotubes, because you can always bullshit a quick explanation for Alien stuff (which doesn't mean it isn't a plothole
, don't kill me, I know what a plothole is, and the egg placement definitely is one, now that you explain the thing), but I don't see a quick explanation for shapeshifting machines.