>>10172440Its the DX renewal version that came out a decade ago or so.
I've see many people in macross fortums complain about this problem specifically for the Alto variant but the actual cause remains unknown, as some claim this happened over the course of years, having the toy exposed in a shelf, while other claim that they never took it out of the box and once they did, surprise, it was yellow.
Maybe it has something to do with the adctual latitude where you live? This issue is also very common in all the Metal Composite Unicorn Gundam figures