So is it that the fuel “will be loaded” that makes the difference? If this deal is actually going forward (and not some publicity stunt), I’m sure the rods are already on site, and have been for awhile.
The fuel rods change significantly the first time the reactor goes critical, not in a loss of particular uranium isotopes, but in the addition of short- and medium-lived reaction byproducts. It's not so much the loading of the fuel as the next step, which might be rushed precisely to create an environmental propaganda victory, that poses a real danger that is different from that due to stored fuel rods.