I thought the reason they stopped selling GF was because during the conversion to Polaris, they couldn't predict which plane would end up actually flying; a converted one or a an old one.
So they announced that these GF seats were selectable for free by J pax with GS or 1K status (then only GS, etc.)
To now suddenly charge $1000 for GF seat selection with only a few non-converted planes left seems rather bizarre.
(Are GS still able to select them for free?)