Not quite, and that has to be the cause of at least half the problems flashing. It's not permitted to lower the variant code when flashing the same firmware version. If gbrm flashes the PR1.2 Asia Pacific (005) firmware, it won't be possible to flash the PR1.2 Europe-1 (001) firmware later. However, it's possible to go in the opposite direction.

Also, there's a lot of product codes, but only 5 generic variants and 5 generic firmware images. I would strongly recommend using variant 001 whenever upgrading to a new version - downloading the images for 059J1Z5 is a safe bet. Telling people to just pick a product code is asking for trouble.

It would be nice if people would stop asking the same questions over and over...much of this thread is "which image should I flash"?