There's no rhyme or rhythm to when the new set goes live, but the typical pattern is that it happens within a few days after a new expansion's announcement
I can only guess that its down to the card being completely symmetrical, since most decks seem to want to use the graveyard in some way
However, the final value can still vary depending on condition, grading score, and overall card authenticity, so high-grade Unlimited copies can still hold significant value
Unleash 10,000,000 Volts with the latest Pokmon TCG Set, Scarlet and Violet: Surging Sparks
This Blastoise was only ever featured in a single interview, which makes it one of the most elusive versions of these test cards